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Alloyed tool and die steels

Tool steels are groups into six types: high speed, hot work, cold work, shock resisting, special purpose and water hardening. High-speed steels are very efficient with heavy cuts and high speeds they are incapable, at slow speeds and lighter cuts, of holding the keen edge necessary for obtaining a very smooth finish on certain articles. Special steels have been produced for this purpose, known as finishing steels, which are capable of retaining a keen cutting edge for much longer periods than carbon steel used under similar conditions.

Bulgarian (BDS) Standards for Steel Materials

This group of Bulgarian (BDS) standards covers carbon, alloy and structural steels, free-cutting steels, plates for pressure vessels, hot-rolled plates, sheets and strips, high-temperature steel castings, welding filler rods, tool steels and electrical quality steels.

British (B.S.) Standards for Steel Materials

This group of B.S. specifications covers carbon and alloy steel plates and forgings used in boilers and pressure vessels, high-strength low-alloy steels, heat-treatable steels, spring steels, sheets and strips. This article also contains standards for various types of steel pipes which specify requirements for high-temperature service, ordinary use, and special applications such as fire protection use. Specifications for steel tubes list standard requirements for boiler and superheater tubes, general service tubes, steel tubes in refinery service, heat exchanger and condenser tubes, mechancal and structural tubing. Steel casting specifications call out the standard properties for pressure purposes. Standards for tool steels, stainless, heat resisting and valve steels are also presented.

Cold Work Tool Steels

Cold work tool steels are essentially high carbon steels, which contain relatively low alloy additions of tungsten, manganese, chromium and molybdenum. These alloy additions increase hardenability, permitting oil quenching with less distortion than with the W series. These are relatively inexpensive steels, and their high carbon content produces adequate wear resistance for short run applications. It is used for all types of blanking and forming dies, gauges, collets, etc.

Cryogenic Treatment of Steel: Part One

Cryogenic treatment of materials has been present in the aerospace industry for over 30 years primarily to enhance the service life of the treated steel.
A number of key factors affect the success of sub-zero treatments including time, temperature profile and tempering practice but used in specific combinations can produce excellent results particularly for wear dependent materials such as tool steels.

Electroslag Remelting Process: Part One

Electro Slag Remelting (ESR) is a process used for remelting and refining of steels and special alloys which are used for critical applications in aircraft, thermal and nuclear power plants, defense hardware, etc.
The prime attribute of the process which differentiates it from other hosts of secondary refining processes is its capability to control both solidification structure and chemical homogeneity simultaneously. The ESR technology is of interest not only for the production of smaller weight ingots of tool steels and superalloys, but also of heavy forging ingots up to raw ingot weights of 165 tons.