The optimization of the tribological properties of the surfaces by means of hardfacing techniques has made great progress in the metallurgical field in recent times. Alloys of the Fe-Cr-C and Fe-C-B type present excellent wear performance under severe conditions, where the incorporation of Nb, Mo and W improves the performance of severe abrasive wear. In this context, new semi-automatic welding consumables have been designed that deposit iron base material of high alloy, with complex carboborides of W, Mo and Cr which present very high hardness and resistant to abrasive wear. The purpose of this work was to compare microstructural variations coupons welded with one or two layers, with or without shielding gas. The chemical composition was measured on each coupon, the microstructure was characterized by X-ray diffraction and scanning electron microscopy. Dilution percentage was determined and Vickers microhardness profiles (HV2) were made on the different phases (HV_0.025). It was found that the dilution with and without shielding gas were 26% and 19%. The hardness was 960 and 1100 HV2. An increase in hardness was observed in the recrystallized areas, as well as a higher percentage of carboborides in the last bead.

近年来，通过表面硬化技术来优化表面的摩擦学性能已在冶金领域取得了长足的进步。Fe-Cr-C和Fe-CB型合金在苛刻的条件下表现出出色的耐磨性能，其中掺入Nb，Mo和W可以改善严重的磨料磨损性能。在这种情况下，已设计出新的半自动焊接材料，用于沉积高合金的铁基材料，以及W，Mo和Cr的碳硼化物，这些碳硼化物具有很高的硬度并具有耐磨性。这项工作的目的是比较焊接有一层或两层有无保护气的微结构试样。测量每个试样的化学成分，通过X射线衍射和扫描电子显微镜对显微组织进行表征。确定稀释百分比，并在不同相（HV）上制作维氏显微硬度分布图（HV2）_0.025）。发现在有和没有保护气体的情况下的稀释度分别为26％和19％。硬度为960和1100 HV2。在重结晶区观察到硬度增加，最后一个焊珠中碳硼化物的百分比更高。