Two types of twin roll caster for casting of fiber inserted composite strip were devised. One is a method using a downward melt drag twin roll caster. It was possible to cast fiber inserted the strip. The fiber was inserted the strip through the puddle formed on the lower roll. Another is a method which was combined the downward melt drag twin roll caster and the melt drag twin roll caster. This method could cast fiber inserted clad strip by pouring different alloy for each nozzle. The fiber inserted composite strip could be cold rolled. The reduction of the fiber and the strip was almost equal. The gap between the fiber and the strip could be improved by the rolling. Reaction between the fiber and the strip was investigated using EPMA.

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Graphite steel has spheroidal or globular form of graphite in steel. The spheroidal graphite cast steel is rich in castability and high damping capacity compared with carbon steel. The effect of mechanical properties and heat-treatment of Fe-1.3%C-1.8%Si-0∿6%Ni investigated. Tensile strength of air-cooled specimen with the Ni free specimen was 870MPa. In the air-cooled, tensile strength decreased with increased in the Ni. In the furnace-cooled, tensile strength increased with increased in the Ni. Microstructure of air cooled specimen to 2%Ni was a pearlite and ferrite around the graphite. The matrix becomes the martensite at 4%Ni.

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The fabrication of Ni-Ti shape memory alloy and magnesium alloy precision screws using by the heading and form rolling have been investigated. The workability of the shape memory alloy and magnesium alloy is extremely poor. Light weight, high strength and non-loosening precision screws are required for cellular phones and notebook PCs. In this study, in particular, the processing limit during heading and the improvement of the dimensional precision of the threads were examined in the detail. Since lightweight and small size are in demand for recent products, the prospect of realizing fabrication technology for the precision micro-screws is discussed.

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Authors have previously proposed the two-step cold extrusion method to form a spur gear. This proposal is made based on the experiment using low-carbon material. In this paper, the effect of materials, five kinds of steel from 0.45% to 1.00% carbon content, for shaping gears by two-step method are reported. The specifications of spur gear examined were as follows : module 1.25,number of teeth 18. Materials used were. It is shown that all materials examined successfully produce a complete teethed spur gear even for high carbon material.

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The temper rolling is applied to eliminate the stretcher strain, to control mechanical properties, to control the surface roughness and to improve the flatness of material rolled. However, there are some unsolved problems remains in analysis of the temper rolling process. The classical rolling theories based on the rigid plastic theory, cannot deal with un-uniform elastic-plastic deformation in the temper rolling process. This paper presents elastic-plastic finite element analysis of stress behaviors in the plane strain temper rolling for annealed high carbon steel sheet. In this analysis, yield point elongation is taken into account for the stress-strain relation of the material deformed. And the calculated rolling forces by FEM are compared with the measured rolling forces by rolling experiment.

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Specific gravity of magnesium alloy is the lightest among practical use metals. Magnesium alloy has many strong physical properties. However, plastic forming is difficult in normal temperature, due to the crystal structure is hexagonal close packed lattice. Most of the magnesium alloy products are produced by casting and thixomolding, and there is extremely little use of plastically deformed material. In this study, the stress-strain behavior of the Magnesium alloy AZ31 sheets was investigated in cold and warm temperatures. The materials are used hot-rolled and hot-extruded ones, to compare the stress-strain behaviors in tension and plane strain compression tests.

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This paper discribes press formability of magnesium alloy extrusions and rolled sheets at room temperature. AZ31,M1 extruded thin sheets and AZ31 rolled sheets are bended at various punch radius. The minimum punch radius at bending was evaluated, and it became clear that the formability of AZ31 extruded sheets are better than AZ31 rolled sheets. And it's minimum punch radius was about 2.5 times of sheet's thickness. But the AZ31 extruded sheets shows the large anisotropic mechanical properties for the orientation of extrusion directions. On the contrast, rolled sheets showed the isotropic mechanical properties.

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Injection tests of mixed wood powders of Cryptomeria with Japanese cypress were carried out at various temperatures and moisture contents of wood powders in order to achieve near net shape forming of wood powders. Effects of cavity temperature and moisture content of wood powders on the injection pressure-punch stroke curve and the mechanical properties of injected products were discussed. The experimental results showed that the wood powders could not be injected into the cavity when the moisture content was 12%. In this case, the profile of injection pressure-punch stroke curve is similar to that of compaction process of wood powders. The bulk density and bending strength of product increase with increasing the cavity temperature. However, maximum relative density became 0.8-0.9 under the cavity temperature of 175±5 ℃. The bending strength of the products made from powders with moisture content 200% tends to be small. On the other hand, the bending strength became max when the powder with moisture content of 50% was used. Finally, it was also found that if the arbitrary cavity was using under appropriate injection conditions, it was possible to obtain the wood powders products with arbitrary shape.

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Recently it has been discovered that the machining process has done a great influence over the occurrence of stress corrosion cracking condition of the austenitic stainless steels. The residual stress and plastic strain of the machined surface has been thought to be the cause of SCC. In order to clarity this problem, we carried out the machining simulation for processing the work material by the finite element analysis and examined the equivalent plastic strain compared to the hardness of machined surface layer of work material.

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Hammering hydroforming is known as an effective method of improving formability in tube hydroforming. However, the factors that cause the improvement are still unclear. This paper presents finite element simulations of hammering hydroforming of an automotive component by the static explicit FEM code, which was developed in this study. The simulated results were compared with those of experiment and showed a good agreement, and this confirmed the validity of the hammering hydroforming simulation by the developed code. The factors that improve the formability were also investigated by simulation. It was clarified that the effect of axial feeding from the edge on the breakage zone improved and as a result thinning decreased.

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This paper deals with twist resulting in two kinds of high strength steel sheet hat channel products consisting of straight portion combined with curved portion in the longitudinal direction. Type-A product is flat. Type-B product is circularly curved in the hight direction. Every type product has unique characteristics in the shape inaccuracy. It could be deduced that twist in type A was mainly generated from residual moment in the curvature of side wall part, and one in type B was mainly generated from residual moment on punch shoulder part.

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Today, it seems that MQL system is started to use not only from environmental issues but also efficient manufacture. Three types of cutting tests were done and compared MQL system with DRY system. The result shows that the cutting force of MQL system is lower than DRY system and on the other hand, the voltage generated by cutting of MQL system is higher than DRY system. It is supposed that the difference between both systems is caused from crack interaction mechanism.

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The influence of heat treatment, working temperature, working rate, lubricant, etc. on the upsettability of AZ61 Magnesium alloy were investigated, in order to makeclear the conditions of warm precise forging. From the warm compression test in axial direction of extruded billet using concentrically grooved tool, the deformation resistance showed work hardening and work softening in following apparent yielding, in not depending on grain size by heat treatment. The peak values of were about 450 and 430 [MPa] at 180 and 200℃ respectively. In every warm upsetting, mushroom deformation in upper portion of upsetted specimen was occurred in the temperature range of 180∿300℃. This mushroom deformation is the peculiar unstable phenomena in extruded AZ61 billet and start in work hardening range.

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Fractal dimension for the ductile fractured surface ruptured at the joint interface is investigated. The simple relationship between the fractal dimension and the dimple size frequency distribution function has been shown analytically as D=α/2. To validate the analytical relationship, the surface profiles of the dimple covered ductile surfaces are virtually formed and their fractal dimension values are calculated. The size distribution of the dimples contained in the formed surface profile is subjected to the power function of the dimple size. Those dimples are arranged randomly. The calculated fractal dimension has qualitatively similar tendency toward the exponent of the distribution function but quantitatively different values. The difference might suggest the necessity of some structure to arrange the dimples.

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This paper describes a new foil welding technique and its experimental results. When an impulse current from a capacitor bank passes through a flat one-turn coil, a magnetic flux is suddenly generated in the coil. Eddy currents are induced in two insulated metal plates and overlapped copper foils (10μm in thickness) between the plates placed in the coil. The foils can be welded both by the magnetic pressure applied onto them and by Joule heat generated in them. The bank energy required for welding of 20mm in length is less than 2kJ.

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The objective of this study is to develop a new method of micro joining using friction stir welding. Trials with micro friction stir welding of magnesium alloys were carried out on a modified milling machine. The results of Micro-FSW performed on AZ31 magnesium alloys were discussed in terms of weldability and weld strength.

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This report describes the joint strength of fine grained steel (FGS) friction welded joints by using the low heat input friction welding method (LHI method) which was developed by authors. The FGS base metals were joined by using the continuous drive friction welding machine with an electromagnetic clutch in order to prevent braking deformation during rotation stop. It was clarified that the friction welded joints with 100% joint efficiency could be obtained by using only the friction stage up to initial torque without the forge (upsetting) stage. That is, the joint tensile strength of the friction welded joints was obtained at the time that the friction torque reached the initial torque. In addition, the joint welded by the LHI method did not cause softening and the grain growth in the heat affected zone. As a conclusion, the LHI method without the forge stage to the FGS base metal welds provides the advantages of less burn-off, less burr, non-softening and less grain growth.

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The Braze-Pressure-Welding with induction heating (BPW) has been developed as a new welding method for joining ordinary steel pipes. In the BPW, a brazing filler interlaid between the mating surfaces melts at the joining temperature, then it is discharged from the joining interface by the welding pressure. The base metals are pressure-welded to each other, and the fillets are formed around the joining area by the discharged filler metals. In the previous papers, it was confirmed that the fillets made only at the outer side of joint area of pipes could relax the stress concentration by finite element analysis. In this paper, it was revealed that the even small fillets made at the both sides of joint area of pipes can relax the stress concentration, and that the fillet transfers the maximum stress site from the edge of the joining interface to the touching point of the fillet and the base material.

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The effects of welding condition on fracture toughness of electron beam welded joint were examined in 2.3GPa grade 18%Ni maraging steel for rocket motor case. In addition, the possibility of toughening by the thermomechanical treatment was investigated. Main results are summarized as follows ; (1) Because the aging precipitates were not solution, when it was kept to aging temperature range before the solution treatment at 1073K for 4ks, the fracture toughness was decreased at either welding condition. (2) In the sample which the welding heat input was the lowest, the fracture toughness was decreased markedly. (3) The fracture toughness is improved by the subzero treatment before heat treatment.

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It is well known that aging characteristics, heat-resistance, superplasticity, mechanical properties and cast structure are remarkably Improved when scandium is added in aluminum and aluminum alloys. However, it is no clear on the effect of adding scandium to the weld zone of aluminum and aluminum alloys. Especially, there are many uncertain points on the aging characteristic of weld zone. Therefore, in this study, the aging characteristics were examined in details on TIG arc weld zone of the Al-Sc alloy, and they were compared with the characteristics of mother metal.

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This paper deals with image sensing of molten pool condition from reverse side, penetration control and arc length control in fixed pipe welding. It is important to control the back bead width properly. Accordingly, a method controlling the back bead width is proposed. As it is difficult to measure the back bead width directly, it is estimated by analyzing the molten pool shape and the dimensions. Furthermore, Neural Network is applied so as to estimate the relations among the shape parameters of the molten pool, welding conditions and the penetration of weld. The back bead width is controlled by controlling the welding current estimated by the output of the Neural Network. As the result of welding control experiments, the effectiveness of the proposed system in the penetration control of fixed pipes is verified.

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In order to estimate the penetration of weld, two methods to monitor the natural frequency of the molten pool oscillation using arc sensor and to observe the pool using visual sensor are proposed and investigated. However, these methods have disadvantages respectively. Accordingly, a new method combining these two methods are proposed. In this study, an advanced penetration control method using information of molten pool oscillation and its shape are developed, and the validity of the control system is verified. The molten pool oscillation is detected by monitoring arc voltage. The shape of molten pool is detected by vision sensor. From the information acquired by two sensors, the molten pool condition is analyzed and a penetration control system is developed. And the validity of the system is verified.

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It is necessary to reduce the hydrogen permeation through the welded joint in order to improve reliability of vacuum apparatus. For the base metal and the weld test specimens of stainless steel SUS304 of various thicknesses, hydrogen permeation quantification tests were carried out. As the result, it was revealed that the permeation quantity at the weld zone was about 4∿6 times of that of the base material. The relationship between the hydrogen permeation quantity and plate thickness was analyzed on the basis of diffusion theory, which showed that the hydrogen permeation flux was inversely proportional to the plate thickness, and this almost agreed with the experimental results.

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An autonomous mobile welding robot system with arc sensor and vision sensor was developed. Especially, control system of automatic seam-tracking, welding current and arc length in real time were constructed. For the seam-tracking system, Hough transform was applied to detect welding line. And welding speed on straight line was changed. So this system can not only detect welding line stably, but also speed up welding process. Neural network for penetration control was constructed. Input parameters including geometric parameters of molten pool were detected from image acquired by vision sensor. In order to keep constant arc length, arc length control system using Fuzzy reasoning was constructed. This autonomous mobile welding robot system was applied to the butt-welding of 1.6mm SPCC mild steel plates.

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Laser processing makes it possible to weld at higher speed and lower strain than the conventional welding method. In recent years, high tensile materials have been developed for automobile industries, but the weld ability of that laser welding is not investigated enough. This paper reports mechanical characteristics of joints welded by two types of laser and a traditional welder.

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AZ31B magnesium alloy plate was welded by YAG laser/TIG arc hybrid welding. Deep penetration with narrow weld bead was obtained by hybrid welding process compared to the TIG arc welding. To estimate mechanical property of hybrid welding for magnesium alloy, tensile test was conducted with butt welded joint. By comparison of welded joint with base metal, it was confirmed that hybrid welded joint has sufficient tensile strength.

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Ggenerally, the deep penetration is often expected for the arc weld metal. However, the shallow penetration in case of purpose such as overlaying and functional thick film to the material surface by the alloying process is required. Penetration shape of weld metal is controlled in the heat transport by the convection of molten metal. The (1)∿(4)force ((1) electromagnetic force (2) friction force by plasma stream (3) surface tension (4) buoyant force) are considered as a driving force of this convection, and the action of this force changes by welding method, welding condition and mother metal, and the shape changes. Therefore, it is not easy that penetration shape of the weld metal optionally is made to change under condition to for give. In this study, the impression of magnetic field was considered as controlling element which positively effected the convection of molten metal. It is anticipated that condition of the arc and situation of the convection of the molten metal change, when it is welded in the magnetic field. Then, we examined how penetration shape of the weld metal changed by carrying out TIG arc welding in the magnetic field.

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Automatic uderwater welding is basic technology to improve cost performance of offshore construction and maintenance. The most important point to keep high weld quality is precise nozzle positioning. Several visual seam tracking methods have been considered to realize autonomous control system. Two typical methods are light cutting method by slit laser beam and ultra sonic imaging technique. Light cutting method is potential method for shape recognition in air condition. Water proofed containers for laser emitter and video camera was prepared for underwater seam tracking of weld line in turbid water. Good seam tracking could be carried out even in turbid water by attached container to shorten the actual light path. Another trial to get clear image by ultrasonic imaging was also reasonable in turbid water.

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In order to improve problems and make use of advantages of the arc welding and the laser welding processes, hybrid welding process combined the TIG arc with the YAG laser was studied . As an experimental result, it was confirmed that the shot position of the laser beam is very important to obtain sound welds in hybrid welding. Therefore, a new intelligent system to monitor the welding area using vision sensor is constructed. Furthermore, control system to shot the laser beam to a selected position in molten pool, which is formed by TIG arc, is constructed. As a result, it is confirmed that the hybrid welding process and the control system are effective on the stable welding of thin stainless steel plates.

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The database of underwater welding technical information has been released via RIO-DB (Research Information Data Base) which is an AIST (National Institute of Advanced Industrial Science and Technology) project. In addition to this, the database of underwater cutting technical information is released. Authors are getting and saving the experimental data which is necessary for making practical underwater processing in the case of construction, repair and removing of ocean rig. As result, a lot of movies of the welding and cutting have been stored. This information is required to be opened to the public as multimedia database. We construct this database as case collections of processing including images of welding and cutting phenomenon. In this paper, we describe outline of database, progress of construction and development in future.

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Is is quite serious problem keeping or progressing manufacturing skills in medium and small companies in Japan. To support the manufacturing skills or techniques, the Digital Manufacturing Research Center has been developing the databases of 15 kinds of processing methods for medium and small companies. These databases will be published on the Internet, and the users will the able to get the useful information or ideas from them. In this report, the authors introduce the database related to welding process.

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Hydroxyapatite (Ca_<10>(PO_4_6(OH_2,HA) is a bioactive material and is synthesized by four kinds of methods. The spark plasma system (SPS) is a promising method to produce advanced materials. Sintering and some chemical reactions are enhanced by SPS. This paper is concerned about the HA synthesis from the mixture of 6CaHPO_42H_2O and 4Ca(OH)_2by SPS. These two compounds are dehydrated under 600℃ and the mixture is turned into the composition of HA. Small crystals of HA were prepared without pressure at 600℃ by heating, but they were decomposed at this temperature for extended times or at higher temperatures. On the other hand, SPS enabled to form stable HA crystals at 600℃, and this growth was based on an effect of SPS. The HA formation was performed at 1000℃ at the high pressure such as 120 MPa. The high pressure of SPS could promote the crystal growth and the stability of HA compared with the decomposition products of HA.

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Research data on the microwave sintering is insufficient, and there still remains a wide unexplored domain. In the present paper refers to experimental studies on ceramics sintering using the 28GHzmm-wave energy generated by a Gyrotron is described. The authors have studies the results of the experiments and wish to present them as data on the production technique of microwave sintering. The results may be summarized as follows : Work material are densified in low temperature and short time by sintering of microwave heating compared with conventional furnace method. The sintered bodies exhibited high density and fine crystalline structured for making uniform temperature of the work piece.

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SiC powders with five different particle sizes were sintered without any additives at temperatures from 1600 to 1800℃ by using a spark plasma sintering (SPS) apparatus. The relative density, bending strength and microstructure were evaluated to investigate the effects of particle size on the properties of SiC compacts. Density analysis results showed that fine 0.34 SiC powders are favorite for sintering higher relative density SiC compact. Bending strength analysis results showed that with decreasing the particle size the bending strength of sintered compacts increased obviously. Composition analysis indicated that the carbon composition at grain boundary was higher than that at matrix for the compacts sintered with 2.4 and 30μm SiC powders. It might suggest that carbon segregation at grain boundaries might favorite the combination of the SiC particles though no extra carbon was added to the starting powders.

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At the solid state bonding of aluminum die-casting alloy, it is important to remove the oxide film at the bonded interface. Focusing on the reduction reaction of oxide film at the bonded interface due to Mg in Al-Mg filler metal at the pulse electric current bonding process, the effect of type of filler metal such as powder, powder formed with polymer and sheet was investigated. The results showed that the tensile strength of the joints with powder was higher than the other type of filler. The usage of powder as filler metal increased the resistance at bonded interface and the temperature at bonded interface was higher than the other type filler. The increase in temperature at bonded interface was introduced to the improvement to quality at the joints with powder as filler metal.

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From the view point of more valuable use of clay and sludge as industry material, ceramics composite materials containing sludge particles of waste were fabricated by an injection molding process. The mechanical property and the quality of the mold parts were investigated by changing the firing instrument with electric furnace or microwave sintering. The experiment results show that microwave sintering instrument is superior to the the elecric furnace as a sintering instrument of the composite material using Kucha clay and α alumina structure sludge.

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New heating process based on high power 28GHz millimeter-wave radiation was reviewed by exemplifying the sintering of high pure alumina and Yb_2O_3-added aluminum nitride. It was indicated that high bending strength over 800MPa (50% higher value than that in conventional sintering method) was obtained in the AKP-20 alumina sintered with millimeter-wave heating. By applying millimeter-wave heating to Yb_2O_3-added aluminum nitride, the aluminum nitride with high thermal conductivity over 200W/(K・m) was also synthesized successfully at 1700℃ for 2-3hr in the reducing atmosphere. It is suggested that these successful results are attributed to so-called "microwave effect", which brings about enhanced mass transfer and electromagnetic force. Capabilities of millimeter-wave heating as the rapid and energy-saving processing for fabricating structural and functional materials are indicated.

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This article describes the evaluation of high-speed superplastic forging and near-net-shape control in nanocrystalline titanium aluminide. The process analysis of isochronal forging at a constant displacement rate permits us to derive the strain rate sensitivity exponent (m) of approximately 0.4 on the basis of the constitutive equation of ε^m=Aδ(1/d)*exp(-Q/kT) for full density nanocrystalline (Ti_<50>Al_<50>)_<90>Fe_<10> with the average crystallite size of 20 nm. For the full density amorphous Ti_<50>Al_<50> sample, the isochronal forging under the constant load leads to a relatively high plastic strain rate of approximately 1×(10)^<-2>s_<-1> at 977K during Newtonian viscous flow that is given by a relation of η=η_0 exp(Q_v/kT) in a supercooled liquid. The apparent activation energy (Q) for nanocrystalline Ti_<50>Al_<50> is derived at 113 kJ・mol^<-1> that is a nearly quarter of the value (467 kJ・mol^<-1> ) of the amorphous alloy. The near-net-shape forging is successfully achieved for the amorphous and nanocrystalline TiAl by using a specially designed carbon plunger.

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An inductively coupled plasma (ICP) was sustained by an internal antenna with insulting covering to assist dc magnetron sputtering. This incorporated a high-density low-energy ion flux to bombard the growing film on grounded Si (100) substrate. Thus, superhard nanocomposite Ti-Si-N and Ti-Cu-N thin films with low residual stress were synthesized at low deposition temperature. Form XRD, TEM and XPS, it was assumed that nc-TiN/a-Si_3N_4 and nc-TiN/nc-Cu nanocomposites were formed, respectively. TiN was composed of nanocrystallite of approximately 20-30 nm. Film hardness strongly depended on the content of Si or Cu, and reached a value higher than 40 GPa in both cases. Hardness enhancement by the addition of Si or Cu could be attributed to nanocomposite effect.

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The pulsed wire discharge (PWD), as one of the applications of pulsed power technologies, has been successfully applied to nanosized powder production. In this paper, preparation of aluminum nitride and copper nanosized powders were carried out by PWD. The average particle size of copper and aluminum nitride were 46 nm and 32 nm, respectively. The ratio of the production mass of powders to the electrical energy consumption was tens to hundreds of g/kWh. Thus, PWD is a very efficient and promising method to prepared nanosized powders.

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The relaxation of compressive residual stress in a diamond-like carbon (DLC) film was achieved by a hybrid process of plasma-based ion implantation and deposition (PBIID), and made it possible to prepare tick DLC film. The compressive residual stress in the DLC film prepared using acetylene gas was decreased with an increase in the negative pulse voltage for ion implantation from 0.46 GPa at no pulsed voltage to 0.16 GPa at the pulsed voltage of -20 kV. The DLC film had about 0.22 GPa that was little dependent on the RF pulse width.

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The trend toward more efficient energy and resource utilization, as well as need for advanced functionality, has led to a growing demand for materials with high erosion and corrosion resistance. In this report, fundamental characteristics of diode laser cladding were examined using a 500W class diode laser systems. The effect of beam characteristics (beam profile, power density, power, etc.) was also examined on the formation of cladding layers

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In this study, ceramic source powders of 3Y-TZP and 3Y-TZP/Al_2O_3 composites, which can show superplasticity during and after sintering were used as insert materials for sinter-bonding of a structural ceramic silico-nitride (Si_3N_4). Temperature, bonding stress, bonding time and thickness of the insert were used as variables for the bonding experiments, and observation on the bonded conditions by SEM, measurement of the 4-point bending strength and analysis of residual thermal stress of bonded specimen by FEM were carried out. The sinter-bonding process and its bonding mechanism are discussed based on the SEM micrograph, bending test result and FEM analysis obtained in present experiment.

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Desktop size superplastic forming machine was developed in order to manufacturing precision machinery parts. It was obtained that superplastic emboss forming part were manufactured by using stacked plate dies.

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Recently, a mobile machines have come into wide use rapidly, and the battery used for these purposes shoud be light and thin. Accordingly a battery case for the mobile phone should also be light and thin deep square shape. In this study, A3003 aluminum alloy was deep-drawn by 13 steps to manufacture a battery case. Mechanical properties and surface conditions of the deep-drawn sheet were investigated. Results obtained in this study show that a good battery case was successfully manufactured for mass production.

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It is well known that the mechanical properties increase rapidly with refining on grain size less than 1μm. In this study, to obtain fine grained materials, we developed a novel high straining process easily applicable to bulk materials, that is, Multi-axial Alternative Warm Forging (MAF), in which the work pieces were rotated by 90°on the longitudinal axis in each forging process performed at 543K for the Al-Mg alloy. The MAFed materials showed a significant developed microstructure having grain sizes less than 1μm. The most of fine grains were surrounded by high-angle and random boundaries. The strength increases with an increase of prestraining without a decrease of ductility. As described above, MAF process is one of the most effective methods to produce fine-grained structure and enhance of its mechanical properties.

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This study is to produce TiC distributed Ti-6Al-4V composite material with fine grain to enhance the strength of Ti-6Al-4V alloy. The dispersed particles Mo_2C to Ti-6Al-4V alloy produced reactive precipitate TiC in the matrix during SPS sintering method. The titanium element has characteristic properties such as hydrogen absorption and dehydrogenation. It was shown that the process combination of particles dispersion and heavy strain work forming for Ti-6Al-4V alloy with hydrides TiH_2 were useful to decrease the grain size. It was found that the microstructure had an average grain size of less than 1μm and those decreased with in increasing of hydrogen content and TiC particles. For specimens with hydrogenation treatment, tensile strength increased more than 1.5 times in comparison with that of non-hydrogenated specimens.

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