WEAR RESISTANCE OF DEPOSITED METAL OF THE TYPE OF CARBON AND CHROMIUM-MANGANESE STEELS UNDER THE CONDITIONS OF DRY SLIDING FRICTION OF METAL OVER METAL

摘要

Parts subjected to intensive wear are made from medium- and high-carbon unalloyed or low-alloyed structural steels. Increased carbon content ensures a high hardness and strength of materials. Because of low-alloying, however, their wear resistance is on a relatively low level. High carbon content considerably complicates the technology of reconditioning the above parts, because of the risk of cold cracking in arc surfacing. To recondition this type of parts it is rational to apply consumables producing deposited metal with the structure of metastable austenite. Such a structure can be produced at application of consumables alloyed by chromium and manganese for surfacing. Preliminary work hardening or work hardening directly during service leads to decomposition of metastable austenite and increase of hardness and wear resistance of the deposited metal. The objective of the work was investigation of wear resistance of deposited metal of chromium-manganese class under the conditions of dry sliding friction of metal over metal. Wear resistance of deposited metal of various alloying systems was studied. It is shown that the correlation between hardness and wear resistance is manifested not in all the cases, both for carbon and for austenitic materials. It is found that materials with the structure of metastable austenite are superior to carbon steels as to wear resistance and are preferable at reconditioning of parts from structural medium- and high-carbon steels.