研究了Ｗ１８Ｃｒ４Ｖ高速钢激光相变强化层的组织和耐磨性能，并对高速钢刀具的切削性能及失效形式进行了分析讨论．结果表明：高速钢经激光相变强化后组织和性能得到了很大的改善，硬度达１００３Ｈｖ０．１以上，且韧性有显著提高，耐磨性提高了２～８倍．刀具激光相变强化后．寿命提高了３～５倍，是以磨损形式失效的。 The microstructure and wear resistance of laser phase transformation strengthened layer of W18Cr4V high speed steel were studied. The cutting performance and failure mode of high speed steel cutting tool were analyzed and discussed. The results show that the microstructure and properties of high speed steel after laser phase transformation have been greatly improved. The hardness is up to 1003Hv0.1, and the toughness is significantly improved. The wear resistance is improved by 2 ~ 8 times. After the laser hardening of the tool. Life expectancy increased by 3 to 5 times, is the form of wear and tear failure.