362 



Tool steel for the united states navy. 



APPENDIX B. 



specifications for high-speed tooiv steel,, for u. s. naval, academy. 



Schedule 3244. 

 Chemical Composition. 



Tungsten... 

 Chromium . 

 Carbon . . . . 

 Vanadium.. 

 Manganese . 



Silicon 



Phosphorus 

 Sulphur . . . . 

 Iron 



Not less than- 



Per cent. 

 16.00 



3.00 



■55 



Not more than — 



Per cent. 

 20.00 



6.00 



•75 



1. 00 



.30 



•35 



.030 



.020 



Remainder. 



The tool steel shall be made in either the electric or crucible furnace. 

 The bars must be forged accurately to the dimensions specified, free from 

 seams, checks, or other physical defects and be of homogeneous com- 

 position. The bars will be delivered in commercial lengths, but bars shorter 

 than 8 feet will not be accepted. 



The tool steel shall be delivered in one shipment. Bars will be selected 

 at random from the shipment, forged into test tools and tested as described 

 below. Samples will be taken for chemical analysis. If these test tools do 

 not show results at least equal to the sample bar tools it shall be considered 

 sufficient cause for rejection of the entire shipment, and the contractor shall 

 replace the shipment within two weeks after receipt of notice of rejection. 



Tests. — The test tool will have a section of f by i^ inches, and will 

 be forged and ground in the form of the No. 30 lathe tool of the Sellers 

 system of tool forms. Each tool will be tested on a nickel-steel forging of 

 about 100,000 pounds tensile strength, with a cut \ inch deep, ^ inch feed, 

 and cutting speed of 45 feet per minute. The tool will be twice reground 

 and re tested. A record will be made of the length of time the tool cuts 

 before it is ruined. This test may be modified at the discretion of the 

 engineer officer. 



