手工具用热冷轧高碳合金钢开发-中国鑛冶工程学会互动式网站.PDF

手工具用熱冷軋高碳合金鋼開發* The Development of Hand-tool Grade Hot-and Cold-Rolled High Carbon Alloy Steels* 1 2 1 1 1 2 1 1 Y. T. Wang S. C. Lin P. K Lee C. Y. Huang High carbon alloy steels are in a good demand for mak ing hand tools that have excellent wear resist ance, anti-high temperature softening, and long life time. When the carbon content is over 0.8 wt% and the alloy additive (0 .8wt%C) is incr eased , the h ard and br ittle net-work of carbides reduces the toughness and suitability for manufacturing. We investigated the carbide spheroidization of the high carbon alloy steels u sing FIB-SEM and computer-aided (FIB-SEM) three-dimen sional (3D) tomography. We con structed the 3D images and clarified the elements contributing to the formation of pearlite spheroiization. To obtain the excellent quality of the high carbon alloy steels, we have (1) added appropriate amount of alloy composites, (2) subj ected the slab to a special hot-rolling process with a low finishing- rolling temp erature and a high coiling temp erature, (3) subj ected the slab to proper annealing temperature for an appropriate time, and (4) subj ected the slab to heat treatment of qu en ch an d t emp er pr oce ss . A fu lly sph er oidiz ed microstructure that has good cold-forming property was obtained. The large amount of chromium and molybdenum carbide dispersed in temper martens