| This study is concerned with the investigation of wear properties of commercial rail steel and high carbon Cr-Ti a1loy steel which is expected to be the new prosperous and energy-saving rail steel. Especially, using rolling contact fatigue test method, the running surface layer of alloy steel and its wear surface were investigated by metallography in detail, in order to clarify the wear behavior of alloy steel. Experimental results showed that the amount of wear of high carbon Cr-Ti alloy steel was half as much as the commercial rail steel. Through the SEM observation of running surface layer, the wear behavior of alloy steel proved to be related to the strain hardening occurring under the wear surface and to voids and microcracks generated in those strain hardened areas as sliding distance increased. The shape of wear debris of this alloy steel showed shallow-rounded sheets. During rolling contact fatigue test, the fatigue cracks of alloy steel were observed as flake type and she11ing damage defects. It has also been thought that those phenomena of alloy steel resulted from pearlite lamella structure of pearlitic steel. |
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