Steel Ltd Research Articles

Die flowability test and weight variations : Y.Seki et al. (Kobe Steel Ltd, Kobe, Japan.)

Die flowability test and weight variations : Y.Seki et al. (Kobe Steel Ltd, Kobe, Japan.)

Sinterability of cemented carbides with aluminium added to binder phase : M. Fukunaga et al. (Kobe Steel Ltd, Akashi, Japan.) J.Japan Soc. Powder and PowderMetallurgy, vol 42, no 4, 1995, 422–426. (In Japanese.)

The development of improved metal powders has been a significant factor in the growth of the powder metallurgy structural parts industry in the last few years. After five years R&D, leading Swedish ferrous powder producer Höganäs AB has released a material, Astaloy CrM®, that it believes will allow further gains. Magnus Johansson outlines the characteristics of the chrome alloy ferrous powder.

Study of sintering by a multifunctional dilatometer: J. Takata, N. Kawai (Kobe Steel Ltd, Takasago, Japan). J. Japan Soc. Powder Powder Metall., vol 41, no 8, 1994, 1012–1018. (In Japanese.)

Study of sintering by a multifunctional dilatometer: J. Takata, N. Kawai (Kobe Steel Ltd, Takasago, Japan). J. Japan Soc. Powder Powder Metall., vol 41, no 8, 1994, 1012–1018. (In Japanese.)

Properties and applications of spray formed aluminium alloys with high silicon contents : M. Saito et al. (Kobe Steel Ltd, Kobe, Japan)

The foregoing sections amply demonstrate the versatility of XTiC and the impressive enhancements in wear resistance that can be achieved by utilizing TiC-based reinforcements. In-house development continues in parallel with customer field trials and specific development agreements as LSM strives to add value to its own and customers' products.

3Cr-1Mo-1/4V-Cb-Ca STEEL

Abstract The 3Cr-1Mo-1/4 V-Cb-Ca ferritic steel is a micro-alloyed version of 3Cr-1Mo alloys for applications at high temperature and high pressures of hydrogen in the petrochemical arena. This datasheet provides information on composition and tensile properties as well as fracture toughness. It also includes information on heat treating. Filing Code: SA-478. Producer or source: Kobe Steel Ltd.

Properties of segregation free powders : H. Suzuki et al (Kobe Steel Ltd, Hyogo, Japan)

Properties of segregation free powders : H. Suzuki et al (Kobe Steel Ltd, Hyogo, Japan)

Mechanical properties of sintered parts made from new low alloy prealloyed powders : M. Yoshida et al (Kobe Steel Ltd Hyogo, Japan)

The silver-palladium(Ag-Pd) alloy coating as a solid lubricant was investigated for its application to the high temperature stud bolts used in nuclear power plants. A hex bolt sample was prepared in the following steps: 1) bolt surface treatment using alumina grit blasting for cleaning and increasing the surface area; 2) nickel(Ni) film coating as a glue layer on the surface of the bolt; and 3) Ag-Pd alloy coating on the Ni film. The films were deposited by using a direct current(DC) magnetron sputtering system. The thickness and composition of the Ag-Pd alloy film have effect on the friction coefficient, which was determined using axial force measurement. A 500 nm-thick Ag-Pd (80:20, molar ratio) alloy film has the lowest friction coefficient of 0.109. A cyclic test was conducted to evaluate the durability of bolts coated with either the Ag-Pd (80:20) alloy film or N-5000 oil. In a cycle, the bolts were inserted into a block using a torque wrench, which was followed by heating and disassembling. After only one cycle, it was not possible to remove the bolts coated with the N-5000 oil from the block. However, the bolts coated with the Ag-Pd (80:20) alloy could be easily removed up until 15 cycles.

Development of laser technology for welding of sintered steel parts: Y. Murai et al (Kobe Steel Ltd, Kobe, Japan)

Development of laser technology for welding of sintered steel parts: Y. Murai et al (Kobe Steel Ltd, Kobe, Japan)

Effect of heat input on the HAZ properties of two duplex stainless steels

Two duplex stainless steel, Avesta 2205 from Avesta AB, Sweden, and Cromweld 3Cr12 from Cromweld Steels Ltd, UK, were welded by shielded metal arc using arc energies of between 0.4 to 1.7 kJ/mm. The effects of varying heat inputs on the properties of the HAZ (heat affected zone), e.g., the hardness, the impact toughness, the tensile strength, the microstructure and the corrosion rate, are documented.

The prediction of properties in heat treated engineering steels

The use of prediction systems is becoming more widespread as the requirements for control of hardenability and properties become more stringent. This paper presents some of the arguments for a more widespread use of the hardenability calculation, along with some techniques currently used for this purpose. In particular, a new method of predicting hardenability from composition is introduced. This ‘Database Method’ has been developed by United Engineering Steels Ltd and British Steel Technical to a position of practical applicability and is able to produce accurate Jominy hardenability curves from a relatively small amount of data (compared with regression analysis). The paper concludes with a discussion of the applications that Rover Group plc have derived from a computer-based hardenability and mechanical properties prediction system, to improving processing parameters, efficiency and product consistency.

High pressure sintering of diamond by a glassy carbon addition : M.Miyamoto et al, (Kobe Steel Ltd. Akashi, Japan). Int. J. Refractory Metals and Hard Materials, No 1 10, No 1, 1991, 27–31

High pressure sintering of diamond by a glassy carbon addition : M.Miyamoto et al, (Kobe Steel Ltd. Akashi, Japan). Int. J. Refractory Metals and Hard Materials, No 1 10, No 1, 1991, 27–31

New 2%Ni-1%Mo steel for high strength components: S. Takajo et al, (Kawasaki Steel Corp, Kawasaki, Japan)

The use of prediction systems is becoming more widespread as the requirements for control of hardenability and properties become more stringent. This paper presents some of the arguments for a more widespread use of the hardenability calculation, along with some techniques currently used for this purpose. In particular, a new method of predicting hardenability from composition is introduced. This ‘Database Method’ has been developed by United Engineering Steels Ltd and British Steel Technical to a position of practical applicability and is able to produce accurate Jominy hardenability curves from a relatively small amount of data (compared with regression analysis). The paper concludes with a discussion of the applications that Rover Group plc have derived from a computer-based hardenability and mechanical properties prediction system, to improving processing parameters, efficiency and product consistency.

Properties and applications of rapidly solidified (RS) Al powder alloy with low thermal expansion and high elastic modulus: H Inoue, S O K Yoshikawa, (Materials Research Laboratory, Kobe Steel Ltd, Kobe, Hyogo, Japan), Kobelco Technology Review, No 8, 1990, 47–50

Anodic oxidation in the wall-jet electrode reactor was performed for three different cast aluminum substrates (i.e. Al 99.80 wt.%, Al-10 wt.% Si, Al-10 wt.% Si-3 wt.% Cu) in order to assess the evolution of electrode temperature under a broad range of current densities (i.e. 3.0–40 A dm− 2). Anodizing was carried out in 2.25 M H2SO4 electrolyte at 25 °C under free and forced convection regimes.At current densities between 3.0 and 15 A dm− 2, corresponding to electrode temperatures lower than 60 °C, the temperature evolution showed the highest values for the AlSi alloy followed closely by the AlSiCu and Al substrates. At larger current densities and temperatures, the temperature sequence changed with the highest values recorded for Al followed by AlSi and AlSiCu alloys. In addition, under these conditions, the oxide layer thickness could not be further increased for any of the three compositions probably due to the severe effects of thermally enhanced field-assisted and chemical oxide dissolution. The changes observed in the thermal effects associated with anodizing of Al at large current densities (i.e. 15 ≥ A dm− 2) were related to the higher rates of conductive heat transfer for Al relative to the other two compositions. The forced convection regime determined a significant decrease in electrode temperature and an increase in oxide layer thickness and anodizing voltage for all three compositions investigated.

3CR12 Stainless steel aid design of Coachwork Walker ambulance and welfare vehicle

3CR12 was introduced into the transport industry by Duple International when, three years ago, they utilised the low cost stainless steel to fabricate the spaceframes for their Integral 425 coaches. Since then 3CR12, which is supplied by Cromweld Steels Ltd, has been used in a wide range of transport applications where the proven structural properties of the steel offer safety, strength and design economy.

INDUSTRY

Thyssen welding seeks new distributors and agents. Thyssen Welding, a product group within the Special Products Division of Thyssen Fine Steels Ltd is looking for distributors and agents.

Seismic design considerations of the properties of New Zealand manufactured steel reinforcing bars

A statistical study is carried out to investigate the probable stress-strain properties of Grade 275 and Grade 380 reinforcing steel manufactured in New Zealand for reinforced concrete construction. The investigation is based on extensive measured data obtained from Pacific Steel Ltd and from University of Canterbury research projects. The results obtained from this statistical study are used to calculate the 5% lower-tail normal probability value of the yield strength, which is considered to be more appropriate for use in the strength design of reinforced concrete members than the specified minimum yield strength. The results obtained from this statistical study are also used to re-evaluate the values of the currently recommended beam flexural overstrength factors used in seismic design in New Zealand, namely 1.25 if Grade 275 steel is used as flexural reinforcement and 1.40 if Grade 380 steel is used as flexural reinforcement. For this purpose, moment-curvature analyses incorporating an appropriate stress-strain model for the steel reinforcement and the Monte Carlo simulation technique are conducted to study the likely increase in the flexural strength above the ideal moment capacity of reinforced concrete members at high curvatures. Improved values for the flexural overstrength factors are recommended.

System for treating radioactive waste : Masaru Hayashi, Atsushi Tagusagawa, Fumiaki Komatsu, Yoshihisa Sawada, Yorihisa Sakaki, Tokyo, Japan assigned to Kobe Steel Ltd

System for treating radioactive waste : Masaru Hayashi, Atsushi Tagusagawa, Fumiaki Komatsu, Yoshihisa Sawada, Yorihisa Sakaki, Tokyo, Japan assigned to Kobe Steel Ltd

4439318 System for treating radio active waste : Masaru Hayashi, Atsushi Tagusagawa, Fumiaki Komatsu, Yoshihisa Sawada, Yorihisa Sakaki, Tokyo, Japan assigned to Kobe Steel Ltd

4439318 System for treating radio active waste : Masaru Hayashi, Atsushi Tagusagawa, Fumiaki Komatsu, Yoshihisa Sawada, Yorihisa Sakaki, Tokyo, Japan assigned to Kobe Steel Ltd

CSD: A Novel Process for Particle Metallurgy Products

The results of development work on a novel particle metallurgy processing technique for highly alloyed tool and high-speed steel manufacture carried out at Aurora Steels Ltd are described. The technique, which employs metal splatting to achieve rapid rates of solidification, overcomes many of the problems and additional operations associated with more conventional powder routes. Conversion of the splatted deposit to finished product is achieved using conventional steelworks processing equipment. Improved hot workability increases the availability of some difficult product forms in highly alloyed high-speed steel grades. Products manufactured using this route have been submitted to extensive quality and performance testing with most encouraging results. Carbide segregation effects normally encountered during conventional high-speed steel ingot processing· are removed, and many other properties, e.g. heattreatment response, toughness, andgrindability, are all substantially improved. End user testing of highspeed steel tools in a number of product forms has demonstrated a consistent and high performance stanqard ..The process has been applied without difficulty to other steel qualities, i.e. austenitic stainless steel, and the product range currently under development includes square, round, and flat bar, forgings, sheet, and other specialist shapes. PM/OI95

Properties of High-Speed Steels Produced by Powder Metallurgy

AbstractThe ‘KHA process’ for producing PM high-speed steels using gas-atomizing equipment and the hot isostatic press has been developed by Kobe Steel Ltd. Measurement of the secondary dendrite arm spacing of gas-atomized powders indicated that the relation between the dendrite arm spacing S II (μm) and the powder particle diameter d (m) was described by S II= K□d where K is a constant. To establish suitable hot isostatic pressing (HIP) conditions with high productivity, density and bending strength were studied in relation to various HIP conditions. It was found that, for example, the combination of 1373K, 40MPa, 30 min was sufficient to obtain full density, but that 1473K, 40MPa, 30min was required to obtain the maximum bending strength. By studying various properties of KHA high-speed steels, it was found that they were superior to the conventional steels for toughness, grindability, and hot workability. Tools such as drills, end mills, hobs, etc. produced from KHA materials exhibited better cutting p...