42 HANDBOOK OF MECHANICAL DESIGN 



HIGH ALLOY CAST STEELS 



Manganese Steel. 



1. Contains 10 to 14 per cent manganese with less than 1.5 per cent carbon. 



2. Extremely hard, strong, and tough, with high resistance to wear. 



3. Usually cast to form, but can be forged at a yellow heat. 



4. Difficult to machine, can be partly softened by quenching from about 1830°F. 



5. Hardness is restored by heating to about 1380°F. and coohng slowly in air. 



Nickel Steel. 



1. Contains ordinarily 0.52 to 3 per cent nickel with 0.15 to 0.60 per cent carbon. 



2. Has high elastic limit and tensUe strength. 



3. Corrosion resistance increases mth the nickel content. 



Chrome Steel. i 



1. Contains usually 0.5 to 3.5 per cent of chromium with 0.2 to 0.6 per cent 

 carbon. 



2. Has high elastic limit, tensile strength, and hardness. 



3. Up to 1 per cent of chromium has httle effect on steel. With 1 per cent car- 

 bon and 2 per cent chromium, great toughness is attained. 



4. Low-carbon chrome steels can be forged with as high as 12 per cent chromium 

 present, but the alloy becomes brittle as the carbon increases. 



5. Chrome steel attains great hardness when quenched in water. 



6. Steels with about 15 per cent chromium are relatively corrosion resistant. 



Vanadium Steel. 



1. Small percentages of vanadium combined with chromium and manganese in 

 steel result in an alloy that has high tensUe strength and elastic hmit. 



2. Vanadium makes nickel steel more homogeneous and decreases the fragility; 

 it is seldom used with more than 8 per cent nickel. 



3. Additions of 0.15 to 0.25 per cent vanadium to chrome steel counterbalances 

 the extreme hardness of chromium and produces an alloy with better machin- 

 ing properties. 



Tungsten Steel. 



1. Is very hard and brittle, difficult to forge, and cannot be welded when the 

 tungsten exceeds 2 per cent. 



2. Can be worked at a red heat, but is usually cast in the form of tools and ground 

 to the desired form. 



3. Addition of tungsten to steel produces a close and uniform structure. 



4. High-carbon tungsten steel retains high magnetism. 



5. Steel alloys with 5 to 8 per cent tungsten are self-hardening. 



