A thermite reaction begins when quartz particles are incorporated into molten aluminum (Al) : the quartz is reduced and the Al is oxidized simultaneously. Consequently, alumina particles are dispersed into the Al-Si alloy matrix to produce a composite slurry. This study investigates the influence of additional elements on the reaction based on the microstructural observation of reacted particles. Magnesium (Mg) and calcium (Ca) were prepared as additional elements ; they served as a wettability modifier to the Al melt. Addition of Mg and Ca promoted dispersion of quartz particles into the molten alloy. Furthermore, Mg addition up to 10 mass% activated reaction. The outer layers of the particles formed a spinel up to 10 mass% Mg addition. However, reaction was significantly suppressed at 20 mass% Mg addition. Such marked retardation of reaction was also observed upon addition of 1 mass% Ca. Addition of Ca or 20 mass% Mg formed dense layers at the surface of quartz particles. The layer formed in the Ca added alloy was identified as CaAl₂O₄ in X ray diffraction (XRD) analysis. Without addition of these elements, the Al as a reducing agent was supplied to the front of the reaction inside the particles through microchannels as a result of the volume shrinkage from quartz to alumina. Reaction retardation by addition of Mg or Ca occurs due to the change in the supply route of the reducing agent from the microchannels to solid diffusion in the dense reactant solid formed at the outer layer of particles.

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  Recently, automobile manufacturers adopt high tensile strength steel for the car body to reduce weight and enhance safety. This is expected to produce considerable automobile steel sheet scraps containing high percentage of manganese (Mn). Mn is known as a graphite inhibitor in cast iron. Consequently. either reducing the Mn percentage or removing the Mn in steel sheet scraps will be necessary for using high Mn steel sheet scraps in cast iron.
  In this study, flake graphite cast iron was produced using high Mn steel sheet scraps. For the purpose of increasing high Mn steel scrap recycling efficiency, Mn was not removed and mechanical properties were investigated. Rare earth element (RE) was added to the melt which included automobile steel sheet scrap (high Mn steel sheet scrap). The specimens were found to satisfy JIS standards and high strength flake graphite cast iron could be produced using high Mn steel sheet scrap as a raw material.
  By comparing with cast iron melt using high purity pig iron high hardness was thought to be caused by the influence of a minor elements.

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  This study aims to clarify the effects of external notch on the impact and bending characteristics of spheroidal graphite cast iron (FDI) and compacted vermicular graphite cast iron (FCV) whose matrix was fully-ferritized by annealing. From each sample we produced five kinds of Charpy-type specimens by adding five kinds of notches whose stress concentration factor (α) varied from 1 (un-notched) to 4.8. They were applied for instrumented Charpy impact testing at the temperature range between 98 K to 423 K and also for three-point-bend testing under a slow loading speed at room temperature.
  The test results of the Charpy impact testing and bend testing showed that the absorbed energy decreases greatly in the range of α from 1 to 2.3 but decreases slightly in the range of α larger than 2.3 in both samples. The results of energy analysis showed that the decreasing tendency of the absorbed energy by adding notches is mainly caused by the decreasing tendency of crack-initiation energy. The degree of influence of the external notches on toughness was found to be larger in the case of FDI than in the case FCV, and also larger in impact testing than in bend testing.

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  Several thousand mass ppm of P and several hundred mass ppm of B are added to cast iron for wear resistant applications. To clarify the behaviors of P and B during solidification of cast iron, the partition coefficients of P and B to primary austenite (κ_P, κ_B) were determined by using secondary ion mass spectrometry. Using these experimental partition coefficients, the solidification process was analyzed on cast irons for brake shoe of railway and marine diesel engine. Both P and B concentrate into the residual liquid, which solidifies in γ + Fe₃C + Fe₃P ternary eutectic structure. B promotes the crystallization of plate-like massive cementite in ternary eutectic. The amount of ternary eutectic could adequately be evaluated by Scheil’s equation and the experimental κ_P.

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  The CaO crucible is expected to serve as a useful tool for melting Ti and its alloys due to its thermodynamic stability. However, there still remain problems that need to be resolved in the melting of Ti and its alloys to enable commercial use.
  The causes of the defects of Ti-6Al-4V alloy castings melted in the CaO crucible were examined and compared with induction skull melting. The key factors of the melting technique using the CaO crucible, affecting the quality of Ti-6Al-4V alloy castings, were investigated.
  Defects of the Ti-6Al-4V alloy castings are caused by the chemical reduction of CaO by Ti. Pressurizing with argon gas in a vacuum induction chamber is effective for reducing the defects. Preheating of the charged material in the crucible and quick pouring into a mold of lower temperature, just after melting down, are important for producing sound Ti-6Al-4V castings.

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  With Japan's launch of its “Action program to prevent global warming” in 1990 and the holding of the United Nation Conference on Environment and Development (the Earth Summit) in 1992, reflecting global efforts to protect the environment, a “high-performance industrial furnace development project” was launched in 1993 by the New Energy & Industrial Technology Development Organization (NEDO).
  This project focuses on the development of a combustion technology which uses air preheated to extremely high temperatures, heretofore considered impossible. This new technology makes use of the recently-developed “high-cycle regenerative combustion system”. We are now further evolving “single regenerative burner”.
  This paper introduces the “single regenerative burner” and “well type melting furnace” recently developed for aluminum alloy castings together with actual examples to demonstrate that this technology can not only reduce carbon dioxide emission, thought to cause greenhouse effects by over 40%, but it can also reduce metal loss by nearly half.

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