Abstract The abrasive wear behaviour of laser metal deposited Fe–28Cr-2.7C alloy with subsequent heat treatments has been investigated. Two heat treatments were applied: (HT1) 1200 °C for 4 h then air cooled to room temperature, followed by 960 °C for 4 h then air cooled, and (HT2) 960 °C for 4 h then air cooled. The abrasive wear resistance of the HT1 condition was significantly higher than that of the HT2 condition. However, the performance of both was inferior to their cast counterpart, despite having similar alloy composition, phases (eutectic M7C3, martensite, and secondary carbide precipitates), and hardness (719–738 HV). HT1 and HT2 samples consisted of a refined carbide structure due to the increase in nucleation and suppression of carbide growth because of the fast solidification rates during the laser deposition process. It was found that the volume loss increased with decreasing carbide size and mean free path between the M7C3 carbides. This was due to the sub-micron globular shaped carbides produced by the laser deposition process being easily fractured or scooped off during plastic deformation caused by the abrasives.

中文翻译：

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热处理对激光金属沉积Fe-28Cr-2.7C合金磨粒和冲蚀磨损行为的影响

摘要 研究了激光金属沉积 Fe-28Cr-2.7C 合金和后续热处理的磨粒磨损行为。应用两种热处理：(HT1) 1200 °C 4 小时，然后空气冷却至室温，然后是 960 °C 4 小时，然后空气冷却，和 (HT2) 960 °C 4 小时，然后空气冷却。HT1 条件的耐磨性显着高于 HT2 条件。然而，尽管具有相似的合金成分、相（共晶 M7C3、马氏体和二次碳化物析出物）和硬度（719-738 HV），但两者的性能均不如铸件。HT1 和 HT2 样品由细化的碳化物结构组成，这是由于激光沉积过程中快速凝固速度导致形核增加和碳化物生长抑制。发现体积损失随着碳化物尺寸和 M7C3 碳化物之间的平均自由程的减小而增加。这是由于激光沉积工艺产生的亚微米球状碳化物在磨料引起的塑性变形过程中很容易断裂或被铲掉。