1.1This specification covers tool steel castings having chemical compositions similar to those of the standard wrought grades.

1.2Several grades are covered and are designated by chemical composition shown in Table 1.

		Composition, %
	Grade	CS-7	CH-12	CH-13	CD-51
Element	UNS	T91907
Carbon		0.45-0.55	0.30-0.40	0.30-0.42	0.85-1.00
Manganese		0.40-0.80	0.75 max	0.75 max	1.00-1.30
Silicon		0.60-1.00	1.50 max	1.50 max	1.50 max
Sulfur		0.03 max	0.03 max	0.03 max	0.03 max
Phosphorus		0.03 max	0.03 max	0.03 max	0.03 max
Chromium		3.00-3.50	4.75-5.75	4.75-5.75	0.40-1.00
Molybdenum		1.20-1.60	1.25-1.75	1.25-1.75	...
Vanadium		...	0.20-0.50	0.75-1.20	0.30 max
Cobalt		...	...	...	...
Tungsten		...	1.00-1.70	...	0.40-0.60
Nickel		...	...	...	...

1.3The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined. Inch-pound units are applicable to material ordered to Specification A597 and SI units for material ordered to A597M.

1.4This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.