Test Piece Representation of Carburized Gear Heat Treatment
Test Piece Representation of Carburized Gear Heat Treatment
Michael A. Pershing
Caterpillar Inc., East Peoria, IL USA
Mohammed Manirizzuman
Caterpillar Inc., East Peoria, IL USA
Abstract
Test pieces are often used for hardened depth and microstructure checks on carburize and harden heat treatment processes so that actual parts are not destroyed for the sake of quality assurance. For gear heat treatment, this is especially important because of costly prior processing. This paper reports on a study to determine the proper size and material of a cylindrical test piece that could be used as an appropriate indicator of the hardened depth and microstructure of the actual gear. Heat treat simulation is used to examine cooling rates for various diameters of test pieces to see how they compare to different modules of tooth sizes on gears. The surface cooling rates up to depths of 1.5 mm are examined to size the test piece correctly.