%0 Journal Article
%T On microstructure and performance of tempered high-boron high-speed steel roll
%A Fu Hanguang
%A Du Zhongze
%A Li Ping
%J China Foundry
%D 2012
%I Foundry Journal Agency
%X Influences of the tempering temperature on the microstructure, mechanical property and wear resistance of High-Boron High Speed Steel (HBHSS) roll materials were investigated by means of optical microscopy, scanning electron microscopy (SEM), X-ray diffraction, hardness measurement, impact tester, tensile tester and pin abrasion tester. The results show that the as-cast structure of HBHSS consists of a great amount of martensite and M2(B,C) and a few retained austenites and M23(B,C)6. After solution treated at 1,050 ˇăC and followed by oil cooling, the amount of M23(B,C)6 carbo-borides in quenched HBHSS increases obviously and the macrohardness of the quenched HBHSS is 66 HRC, which is very close to the 65.8 HRC of as-cast HBHSS. On the whole, the hardness of HBHSS alloy shows a trend of slight decrease with increasing tempering temperature when tempered below 500 ˇăC. While when above 500 ˇăC, the hardness increases slightly as the tempering temperature increases and reaches a peak at 525 ˇăC and then decreases obviously. The impact toughness of HBHSS has a tendency to increase as the tempering temperature increases. Tempering can improve the tensile strength and elongation of HBHSS, but a higher tempering temperature causes a slight decrease in both tensile strength and elongation. Excellent wear resistance can be obtained by tempering at 500 to 550 ˇăC.
%K high boron high speed steel
%K tempering temperature
%K carbo-boride
%K metallic matrix
%K mechanical property
%K wear resistance
%U http://www.foundryworld.com/uploadfile/2012082747437861.pdf