论文部分内容阅读
利用金相显微镜(OM)、扫描电镜(SEM)和X射线衍射仪(XRD)分析不同激光工艺参数重熔后的Ni基合金火焰喷焊层及其经不同温度回火处理的显微组织和相组成,并进行了显微硬度和耐磨性测定。试验结果表明,重熔喷焊层的组织主要由γ-(Ni,Fe)固溶体和Cr23C6,Cr7C3,Cr2B,CrB,Cr5B3,Fe3B,Fe2B等相组成,与火焰喷焊层相比,显微组织得到进一步细化,硬度和耐磨性都有较大幅度的提高。在相同工艺条件下,激光扫描速度愈快,显微组织愈致密、细小,硬度和耐磨性愈好,但重熔喷焊层的熔深较浅;不同激光工艺参数的重熔喷焊层,经不同温度回火后,硬度都得到了进一步的提高;扫描速度为360 mm/min,经600℃×3 h回火后的重熔喷焊层硬度相比为最高。采用合适的激光重熔处理工艺及随后的热处理,可使Ni基合金火焰喷焊层进一步强化,使用性能得到进一步改善。
The microstructure of the Ni-based alloy flame sprayed layer and its tempering treated by different temperature were analyzed by OM, SEM and XRD. Phase composition, and the determination of microhardness and wear resistance. The results show that the microstructure of the remelted spray coating consists of γ- (Ni, Fe) solid solution and the phases of Cr23C6, Cr7C3, Cr2B, CrB, Cr5B3, Fe3B and Fe2B. Further refinement, the hardness and wear resistance have more substantial increase. Under the same process conditions, the faster the laser scanning speed, the denser the microstructure, the smaller the hardness and wear resistance. However, the remelting sprayed layer has a lower penetration. The remelting sprayed layer with different laser process parameters After tempering at different temperatures, the hardness has been further improved; scanning speed of 360 mm / min, after 600 ℃ × 3 h tempering the remelting spray coating hardness compared to the highest. Using appropriate laser remelting process and subsequent heat treatment, Ni-based alloy flame spray coating can be further strengthened, the use of performance has been further improved.