巻号一覧
40 巻, 1 号
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林 宏爾1993 年 40 巻 1 号 p. 2
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (82K) -
田島 俊造, 鈴木 裕之, 黒木 英憲1993 年 40 巻 1 号 p. 3-7
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーCompacts are formed by pressure (0.9MPa) slip casting from a submicron Al2O3 powder using sheet filter. The process is compared with the conventional one using plaster mold. Two types of filters are ; 1. acetyl-cellulose sheet with the thickness of 125μm and the hole size of 0.2μm backed by a plate of porous aluminum ; 2. plaster mold reinforced by analuminum tube. An Al2O3 powder with the average particle size of 0.22μm and the purity of 99.99% is dispersed in a ball mill to prepare slips with coefficients of viscosity in the range of 400-600mPa⋅sec.
The results obtained are summarized as followes:
1.The rate of increase in the depth of the cake formed from the slip is represented by a constant K=L2/t(L:the thickness of the cake [mm], t:the time [min]).The value of K is 0.08mm2/min in conventional slip casting with the plaster mold and about 1.0mm2/min in pressure slip casting with the plaster mold or the cellulose sheet.
2.The sintering of the compacts are obstracted by the contamination from a plaster mold. The thickness of the contaminated layer in the compacts is about a few millimeter from the cake-mold interface.
3.Density of 99 to 99.5% and bending strength above 700MPa are obtained in the alumina compacts sintered at 1250°C for 1.5hr, in the pressure slip casting with the acetyl-cellulose sheet filter.抄録全体を表示PDF形式でダウンロード (3011K) -
圧縮軸方向密度分布への影響鶴 英明, 中川 威雄1993 年 40 巻 1 号 p. 8-11
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーWater-atomized high speed steel powder was pressed into a component with high aspect ratio by repetitive compaction process using electric drive CNC press and the uniformity of green density along the compacting axis was investigated. For the dimensional accuracy the uniform density distribution is very important because of large linear shrinkage ratio of about 10% during vacuum sintering. The CNC compacting press has superior versatility of compaction sequences and makes it possible to minimize the difference of local green density by repetitive compaction which consists of several sets of powder filling and compaction.
The green compact(φ14×45) by repetitive compaction showed fairly uniform density distribution and smaller local density variation compared with green compact by conventional single compaction. The measured profile curves along a side wall of sintered parts were in good agreement with the predicted density distribution and the dimensional variation in radial direction was reduced. Tensile strength was equivalent to that of conventional part and the breakage didn't occur at the joining point. The experimental results shows the possibility of near-net-shape production of P/M high speed steel parts with large height.抄録全体を表示PDF形式でダウンロード (2136K) -
田島 俊造, 松永 英幸, 黒木 英憲1993 年 40 巻 1 号 p. 12-15
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーIn the centrifugal compaction process of ceramics, shapes of the compacts may be limited because the centrifugal force acts only in one direction of each compact. The uniformity and soundness of the compacts are investigated by comparing their different parts packed with particles moving at a right angle or in the reverse direction to that of the centrifugal force.
An AlSUB>2OSUB>3 powder with the average particle size of 0.22μm and the purity of 99.99% is dispersed in a ball mill to prepare slips with the water content of 25% and coefficients of viscosity in the range of 400-600 mPa.s.
The compacts are examined for moisture, green density, ignition loss and 1250°C-1.5hr sintered density, and proved to be uniform without taking any measure when they are packed by the right-angle movement. They also become uniform by the reverse-direction movement when the top end of the die cavity is provided with vents for air and supernatant.
The centrifugal compaction process can be used to obtain sound and uniform compacts with various shapes by sintering at 1250°C for 1.5hr.抄録全体を表示PDF形式でダウンロード (3558K) -
趙 源丞, 林 宏爾1993 年 40 巻 1 号 p. 16-19
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーThe effect of uni-directional orientation of SiC whisker(SiC(w)) on the pressureless sintering dens cation of SiC(w)/Si3N4 ceramics composite was investigated in relation to the content and aspect ratio of SiC(w) and the amount of sintering aids. It was found that the uni-directional orientation was effective for promoting the densification at higher SiC(w) contents. The maximum relative density obtained, however, was limited to 92 and 86% at 15 and 20vol%SiC(w), respectively.抄録全体を表示PDF形式でダウンロード (1444K) -
趙 源丞, 林 宏爾1993 年 40 巻 1 号 p. 20-23
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーMicrostructures of SiC whisker/(Si2N4-4, 8, 12mol%Y2O3 6mol%Al2O3) composite ceramics were examined by high-resolution transmission electron microscope. No evidence of interfacial reaction both between SiC whisker and grain boundary phase and between SiC whisker and Si3N4 was observed, irrespective of Y2O3 content. Therefore, the conclusion in the previous study that the variation of the mechanical properties of SiC whisker/Si3N4 composite ceramics with increasing Y2O3 content was mainly due to the variation or change in the size of acicular Si3N4 grains and the kinds of the grain boundary phase was considered to be correct.抄録全体を表示PDF形式でダウンロード (4545K) -
西田 俊彦, 宮崎 尚子, 斉藤 裕美, 浦部 和順1993 年 40 巻 1 号 p. 24-28
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーEquimoler mixture of Ti and C powders with additions of 5-40 wt% of Al2O3 powder was molded by using an pressure-resistant metalic mold whose inner wall was covered with a carbon insulator. The mixture in the mold was ignited by a tungsten heater and, then, compressed under a pressure of 1 GPa (10000 atm). TiC-Al2O3(10wt%) body thus obtained had a microstructure in which TiC crystals of relatively small grain size were surrounded by non-crystalline phase con-taining Al2O3, and the maximum value of its Vickers hardness was 32.7 GPa.抄録全体を表示PDF形式でダウンロード (2586K) -
篠原 耕治, 植田 文洋, 棚瀬 照義1993 年 40 巻 1 号 p. 29-32
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーThe linear thermal expansion coefficient (α) and the thermal conductivity (κ) of cemented carbides are very important properties for hot wear resistant tools. The effects of various structural factors such as binder content, carbon content, WC grain size and composition of binder on those parameters were studied.
The results obtained were as follows. The α values were proportional to binder content only. They were hardly affected by WC grain size, carbon content of the alloy, and composition of binder. In the case of WC-Co alloy, the κ values decreased with increasing Co content and with decreasing WC grain size and carbon content of the alloy. The κ values of WC - Co - Ni - Cr alloy were lower than those of WC-Co alloy at the same structural factors.抄録全体を表示PDF形式でダウンロード (215K) -
山本 勉, 平井 龍哉, 高柳 文雄, 上野 和夫1993 年 40 巻 1 号 p. 33-37
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーFracture toughness has been recently considered to be one of the important mechanical properties in the same way as transverse-rupture strength for sintered hard materials such as ceramics, cermets and cemented carbides. The measuring method of fracture toughness was established according to JISR1607 in 1990 for fine ceramics, but it has not been established for cermets and cemented carbides. Therefore, fracture toughness of TiC-TiN based cermets, K-grade and P-grade cemented carbides with different metal binder content or WC grain size were measured by SEPB method according to JISR1607 for comparing with that of ceramics. And also, the effects of various notches for inducing precrack on fracture toughness and the relations between groove width of anvil and load for inducing precrack or length of precrack were investigated. Fracture toughness of cermets and cemented carbides increased with increasing metal binder content or WC grain size. With the same metal binder content, the amplitude of the fracture toughness showed the following order : K-grade cemented carbides > P-grade cemented carbides > cermets. These results were discussed from the standing point of mean free path of metal binder phase and young's modulus of the alloy.抄録全体を表示PDF形式でダウンロード (1585K) -
駒井 正雄, 礒部 剛彦, 高木 研一1993 年 40 巻 1 号 p. 38-43
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーEffects of Cr on the mechanical properties and phase formation of WCoB base alloys were studied using the model alloys whose compositions were Co-1.93mass%B-33.3mass%W-(0-20)mass%Cr. The new alloys consist of a WCoB type ternary boride as a hard phase and a cobalt base binder alloyed with Cr, W and other elements, both of which are formed by reaction boronizing sintering.
The transverse rupture strength (TRS) of the alloys depended strongly on the microstructure, which varied significantly with Cr content. The highest TRS of 2.85GPa obtained at 15mass%Cr was attributed to the refinement and good distribution of WCoB boride. Moreover, the TRS of the alloy with 15mass%Cr still kept a value of about 1.8GPa at 1173K. The weight gain of the alloy oxidized in air at 1173K was less than that of SKD11 and close to that of SUS304.
Corrosion resistance of the alloys in a non-oxidizing 10mass% HCl solution was better than those of a PM high speed steel, stainless steels such as JIS SUS 405, 440C, 316L and 304 and a tool steel JIS SKD11, and close to that of Hastelloy C. On the other hand, in an oxidizing 10mass% HNO3 solution the alloys showed better corrosion resistance than a cemented carbide of WC-10mass%Co, a PM high speed steel and SKD11, and were almost same as stainless steels and Hastelloy C.抄録全体を表示PDF形式でダウンロード (1251K) -
複合快削性セラミックス千徳 英一, 柏本 浩伸, 中 勉, 藤村 善雄1993 年 40 巻 1 号 p. 44-48
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーThe machinable ceramics are used for mechanical and electronic parts. These ceramics consisting of fluor-phlogopite can be machined with tight tolerance using conventional metal cutting equipment and tools. The mechanical properties of these ceramics drops at high temperature. The purpose of this paper is to develop compound machinable ceramics of high strength at higher temperature than the transition temperature of glass and to observe machinability of these ceramics. The sintering of compound machinable ceramics have been carried out on the powder mixture of machinable ceramics and ZrSiO4.
The main results obtained were as follows : (1) The compound machinable ceramics showed good mechanical properties at high temperature. (2) The addition of ZrSiO4 powder in the ceramics increased high temperature strength. (3) The higher machinability by turning test was obtained for ceramics with ZrSiO4 amounts ranging from 0 wt% to 40 wt% . (4) The tool life showed a maximum at the cutting speed of 50 m/min.抄録全体を表示PDF形式でダウンロード (2474K) -
西山 勝廣, 佐川 慎悟, 小嶋 琢, 梅川 荘吉1993 年 40 巻 1 号 p. 49-52
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーSliding friction experiments were conducted on SiC, Si3N4 B4C-TiB2 and Al2O3 ceramics under the condition of sliding contact with themselves in air. The test conditions included temperature up to 800°C., maximum surface velocity of 1.14m/min, and normal forces ranging from 4.31N(0.44kgf) to 104.57N(10.67kgf). Friction coefficient as low as 0.09 to 0.1 was obtained at 800°C for boron carbide-titanium diboride. The wear rates of Si3N4, SiC and Al2O3 ceramics increased with increasing temperature. However, the wear rate of B, C-TiB, decreased with increasing temperature. For most of the sliding pairs, the wear rate was in the range of 10-5mm3/Nm to 10-4mm3/N-m, the single exception being a value of 10-8mm3/N-m recorded for B4C-TiB2 at 800°C. The implications of wear mechanism for these results were shown.抄録全体を表示PDF形式でダウンロード (2208K) -
三浦 秀士, 本田 忠敏, 柳下 紀, 渡辺 忠彦1993 年 40 巻 1 号 p. 53-57
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーThe resistance of seven diboride ceramics mixed with Zr or CoB as sintering aids to corrosion in liquid Al at 750°C was investigated by the immersion test, and their microstructures were characterized.
The TiB2 system ceramics showed good resistance by the formation of thick oxide case TiO2(>100pm) which inhibit the penetration of liquid Al. On the other hand, the ZrB2 and the HfB2 system ceramics were readily attacked by liquid Al even in the short immersion time (<100hr). This seemed to be due to the spalling of oxide case and the formation of Al3Zr which cause localized swelling at the grain boundaries and interfaces and result in failure. Therefore, it is unsuitable for the diboride system ceramics to mix with Zr as far as the resistance to corrosion in liquid Al is concerned.抄録全体を表示PDF形式でダウンロード (4862K) -
藤森 哲雄, 山本 恭永, 岡田 厚正1993 年 40 巻 1 号 p. 58-61
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーThe synthetic diamond which is used for some cutting tools is known to reduce its strength after heating at an elevated temperature above 1200K. In this study, the Cu-P system alloy which has the eutectic reaction at 987K is proposed as a bonding material for sintering of diamond tools. Samples sintered at 1110K-1190K with several kinds of Cu-P system alloys were observed by a SEM and an EPMA, and investigated through a hardness test and a bending test. As the result, it was clarified that the thermal degradation of diamond can be prevented by the low temperature sintering with the Cu-P system bonding material, and the ratio of good diamond in tips increases with decrease of sintering temperature by means of applying the low melting Cu-P system alloy.抄録全体を表示PDF形式でダウンロード (2285K) -
小林 慶三, 高柳 猛, 三輪 謙治1993 年 40 巻 1 号 p. 62-65
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーHard metals containing small amounts of cobalt were prepared by mechanical alloying using a vibrational ball mill in Ar atmosphere under reduced pressure. The contamination in the hard metal during mechanical alloying was attributed to wear of vibrational balls and could be reduced by using hard metal balls. Although mechanical alloying treatment was effective for the hard metals containing less than 3 mass%Co, increasing in cobalt content resulted in the formation of η phase (Co3W3C).
A mechanical alloyed WC-lmass%Co hard metal, sintered at 1773K for 1.2ks in a vacuum, showed finer structure and higher hardness than a mixed WC-1mass%Co one.抄録全体を表示PDF形式でダウンロード (2456K) -
徳本 啓, 北田 哲則, 東明 広宜, 坂口 茂也1993 年 40 巻 1 号 p. 66-71
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーTi-Mo-(33-80)mass%TiC alloys were prepared through P/M technology and their micro-structures and mechanical properties were investigated. These alloys were revealed to have two phases, those were TiCx phase and β-Ti phase. The lattice constant of TiCx was increased with increasing TiC content, associating with increase of x. On the other hand, increase of TiC content decreased the lattice constant of β-Ti due to increase of Ho content in β-Ti. Furthermore, increase of TiC content increased hardness of the alloys but slightly decreased transverse-rupture strength. It was concluded that Ti-Mo-45mass%TiC alloy had better combination of hardness and transverse-rupture strength than that of conventional Ti-Mo-33mass%TiC alloy.抄録全体を表示PDF形式でダウンロード (3128K) -
篠原 信幸, 白井 伸二, 村井 誠1993 年 40 巻 1 号 p. 72-75
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーWe developed a new type of hard alloy which was prepared by sintering of the powder mixture of pure W, TiB2, and ternary complex boride Mo2NiB2 powders with composition of W(bal.)-10vol%Mo2NiB2-(0-13)vol%TiB2 under the pressure of 0.98MPa Ar gass at 1973K for 1.8ks. Mechanical properties such as hardness, fracture toughness, transverse rupture strength, thermal shock resistance and sliding wear resistance were in-vestigated on this hard alloy. Moreover, corrosion resistance of the hard alloy in a molten Al alloy (JIS ADC10) at 1023K was examined.
The result indicate that the hard alloy has better sliding wear resistance against FCD45 than SKD61 and excellent corrosion resistance in the molten Al alloy. We expect that the hard alloy will be used as many machine parts for aluminium diecasting.抄録全体を表示PDF形式でダウンロード (1264K) -
日高 謙介, 田中 完一, 西村 信一1993 年 40 巻 1 号 p. 76-79
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーNew chromium base hard-facing alloys are Cr-Ni-X system alloys containing more over 50% by weight of chromium, where X represents small amounts of molybdenium, boron, and silicon.
In this paper, these alloys(717, 737) were investigated in hardness, impact value, wear resistance, corrosion resistance, and weldability for PTA process, compared with those of conventional cobalt base alloys(CoCr-A, CoCr-B) and nickel base alloy(NiCr-B). The results were summurized as follows:
1) These alloys had enough hardness and impact value as hard-facing alloys.
2) Wear resistance of these alloys were better than that of conventional cobalt base alloys and nickel base alloy.
3) Corrosion resistance of these alloys were superior to conventional cobalt base alloys and nickel base alloy. In particular weight losses in 5%H2SO4. 65%HNO3, and 90%Na2SO4+10%NaCl molten ash were negligible.
4) These alloys had good weldability for PTA process in the same manner as convensional cobalt base alloys.抄録全体を表示PDF形式でダウンロード (2252K) -
松本 史朗, 加藤 周一郎, 冨井 洋一1993 年 40 巻 1 号 p. 80-84
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーA chemical vapour deposited diamond film was grown on a SiC substrate by the plasma arcjet method. The deposited film was circular and appeared to be radially zoned by visual examination. Hicrofocus Raman spectroscopy was used to examine the radial compositional variation of the film and SEM was used to examine the surface morphologies corresponding to the various zones. Raman spectra showed that the composition varied from graphite to diamond while being hydrogenated carbon. SEM observation showed that amorphous carbon was hydrogenated into hydric carbon, and that included a microcrystalline diamond and prevented the growth of the diamond. As a result, a microcrystalline diamond film zone was produced between graphite zone and polycrystalline diamond zone. The structure and indentation hardness of the microcrystalline diamond film were investigated by TEN observation and micro-Vickers, and also the effect of the microcrystalline diamond film on the overlaped diamond film was investigated by SEM, XRD, Raman spectroscopy. The results were as follows.
(1) The hydric carbon in microcrystalline diamond film looked the matrix material that surrounded the single crystalline diamond of 10-20nm size by TEN bright-fild image and TED pattern.
(2) The micro-Vickers hardness of the microcrystalline diamond film was 82 GPa with a load of 9.8N at room temperature. The indentation was characteristic of amorphous structure.
(3) The overlaped diamond film on the microcrystalline diamond film layer exhibited flat surface and good crystallinity.抄録全体を表示PDF形式でダウンロード (3422K) -
李 忠孝, 福永 俊晴, 水谷 宇一郎1993 年 40 巻 1 号 p. 87-91
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーThe ambient temperature effect on mechanical alloying was studied using a mixture of copper and tantalum powders at a composition ratio Ta:Cu=7:3. This system is characterized by a positive heat of mixing of 2kJ/mol. We confirmed that the higher the ambient temperature during milling, the faster the amorphization proceeds. This thermally assisted amorphization(TAA) becomes noticeable after 60 hours of milling. In addition, we found the evidence for the TAA by annealing a partially amorphized MA powders at temperatures below the crystallization temperature. These results were discussed in terms of thermodynamics.抄録全体を表示PDF形式でダウンロード (285K) -
黒田 名里子, 福永 俊晴, 水谷 宇一郎1993 年 40 巻 1 号 p. 92-95
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーMechanical aloying(MA) under the N2 gas atmosphere was capable of amorphizing V70Cu30 powders which is characterized by a positive heat of mixing (ΔHmix=5 kJ/mol). The S(Q) observed by X-ray diffraction gradually changed into the structure characteristic of an amorphous state with increasing milling time. The S(Q) observed by neutron diffraction after 200 hours of milling possesses a mixture of both amorphous and crystal phases. Since the coherent scattering length of the V atom in the neutron diffraction is negligibly small, small crystal peaks shoud be due the Cu crystal. The growth of a new peak at Q=4.25 A-1 in the S(Q) was observed after 40 and 120 hours of milling and then it disappeared after 200 hours of milling. This peak is attributable to the bcc Cu crystal formed by dissolving Cu atoms into the bcc V lattice. The results can be interpreted that the bcc solid solution is formed at the early stage of milling but becomes amorphized due to the gradual incorporation of N atoms in the subsequent stage of milling.抄録全体を表示PDF形式でダウンロード (240K) -
福永 俊晴, 岡坂 和遵, 水谷 宇一郎1993 年 40 巻 1 号 p. 96-99
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリー(Ti76Ni24)x(Ti70Cu30)1-X neutron zero scattering amorphous alloys were synthesized by mechanical alloying. The concentration-concentration correlation functions of the alloy systems could be directly observed by neutron diffraction, because the averaged neutron scattering amplitudes of the amorphous alloys are set to be zero. The chemical short range order parameter a calculated from the Warren definition turns out to be negative for all pseudo-binary Ti-(Cu, Ni) amorphous alloys. The value of a is found to rapidly decrease with increasing Ni content. The results indicate that an increase in the chemical short range order by alloying with Ni element is ascribed to the stronger affinity of a Ni atom with a Ti atom than a Cu atom. Moreover, it was found that the chemical short range order strongly affects with the thermal properties, i.e., the crystallization temperature and the enthalpy of crystallization.抄録全体を表示PDF形式でダウンロード (240K) -
師岡 利政, 湯浅 栄二, 松本 修1993 年 40 巻 1 号 p. 100-104
発行日: 1993/01/15
公開日: 2009/05/22
ジャーナル フリーCu-Ti-B powders prepared by mechanical alloying were compacted and then sintered in a temperature range of 873-1273K. Changes in microstructure and mechanical strength of the sintered comacts with the sintering were investigated. Inter-metallic compound TiB2 is formed through the sintering. The formation of TiB2 phase is accelerated with increasing of sintering temperature. When the compact was sin-tered for prolonged time at high temperature, copper-rich grain is formed at contact region between the particles. Result of hardness measurement in the sintered com-pacts exhabits two peaks with sintering time in the temperature range of 873-1073K. The hardness value reachs the first peak in less than about 20ks and the secound peak requires longer sintering time than 70ks. Both peak values of the hardness decrease with the increasing of sintering temperature. It is confirmed by three-points bend-ing test that bonding strength between particles increases with increasing of sintering time.抄録全体を表示PDF形式でダウンロード (4361K) -
金子 武1993 年 40 巻 1 号 p. 105-111
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーSystematic studies were carried out on the compressive effects of Ta single crystals grown by electron beam melting methods. Stress-strain curves of various Ta single crystals were obtained in order to clarify the effect of compressive deformation. According to the stress-strain curves and surface observation, the following results were obtained.
It was cleared that the work hardening effect of Ta single crystals, examined by using compression tests, was determined to be, smaller in the order of directions <100>, <111>, and <110>, and also smaller in the order from <111> to <110>, and from <100> to <110>, as it was the the same as the Fe single crystals.抄録全体を表示PDF形式でダウンロード (1127K) -
坂本 卓1993 年 40 巻 1 号 p. 112-117
発行日: 1993/01/15
公開日: 2009/12/04
ジャーナル フリーMo powder compacts are generally sintered at high temperature by direct sintering method. Recently instead of this method, the activated sinterings are studied, in order to promote the densification of No powder compacts.
We investigated the behavior of No powder compacts which are activated by the addition of B4C powder. The results of this experiment are as follows:
1)Sintered No powder compacts are slightly activated by the addition of B4C powder.
2)With an increase in sintering temperature, compounds of Mo-B boride and Mo-C carbide are pro-duced in the sintered No powder compacts.
At next time, we added Ni and B4C powders to Mo powder compacts and sintered. Following results were obtained:
3)The liquid phase is produced at sintering. This liquid phase is brought by the eutectic reaction of Ni-B boride which is combined Ni powder with B element of B4C powder.
4)The hardness of the sintered No powder compacts with addition of Ni powder gets Hv2300.抄録全体を表示PDF形式でダウンロード (3189K)
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