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采用双筒双路送粉法研究了WC含量(体积分数)分别为0%,9%,18%,27%,36%,45%,54%,72%和100%时 Stellite 6＋WC的激光熔覆,在E24低碳钢上熔覆的Stellite 6＋WC涂层微观组织演变中发现了两种明显不同的凝固特征,第一种凝固特征以先共晶枝晶和枝晶间共晶为主导．WC含量从 0-36%,加入的WC完全溶解,凝固组织包含α-Co,σ-CoCr和M7C3类碳化物,第二种凝固特征以各种块状、花状、蝴蝶状及星状析出物和基体为主导, WC含量从 45%-100%,大部分WC溶解,基体中最高W含量(质量分数)为26%左右．析出物中的最高W含量达 64. 6%,微观组织包含 WC,Co和各种Co-W-C/Fe-W-C复杂碳化物,激光熔覆纯WC时出现了许多内部含W约91%,外围含W约68%的特殊块状组织．可能是包晶反应冻结的产物。
The laser melting of Stellite 6 + WC with WC content (volume fraction) of 0%, 9%, 18%, 27%, 36%, 45%, 54%, 72% and 100% Two distinctly different solidification features were found in the microstructure evolution of Stellite 6 + WC cladding on E24 low carbon steel. The first solidification feature was dominated by the first eutectic dendrite and interdendritic eutectic. The WC content is 0-36%, the WC added is completely dissolved, the solidified structure contains α-Co, σ-CoCr and M7C3 carbides. The second solidification feature is precipitated in various lumps, flowers, butterflies and stars Materials and matrix dominated, WC content from 45% -100%, most of the WC dissolved, the matrix W highest content (mass fraction) of about 26%. The maximum W content in the precipitates reached 64.6%. The microstructure contained WC, Co and various Co-WC / Fe-WC complex carbides. When laser cladding pure WC, Containing about 68% of the special block of W tissue. It may be the product of peritectic reaction freezing.