Ni-Cr合金真空钎焊金刚石工具基体热损伤分析
2019-06-19
作者：蒋城杰，毛人杰，徐佳宁，聂大明，宗福乐，孙宝军
单位：台州学院
摘要：为研究高温钎焊金刚石工具时基体所受的热损伤对同种材料不同热处理状态下的工具基体进行分析与检测。基体材料选择45钢制作试样，对原始试样、真空炉中干烧至钎焊温度的试样以及与金刚石钎焊后试样的显微结构和显微硬度进行检测与对比分析；对原始试件和真空干烧过的试件进行拉伸性能试验，并用扫描电镜（SEM）对断口形貌进行观察。结果表明：45钢基体经高温真空干烧和钎焊后，晶粒粗大，致使强度、硬度、塑性等力学性能大幅下降，基体材料出现严重的热损伤。研究成果可为钎焊金刚石工具基体材料的选择和钎焊工艺的制定提供试验和理论依据。
关键词：钎焊；金刚石工具；基体；热损伤
中图分类号：TG401；TH161文献标志码：ADOI：10.3969/j.issn.1000-7008.2019.06.012
Analysis on Thermal Damage of Substrate for Brazing Diamond Tool
with NiCr Alloy in Vacuum Furnace
Jiang Chengjie，Mao Renjie，Xu Jianing，Nie Daming，Zong Fule，Sun Baojun
Abstract:In order to investigate the thermal damage of the substrates during brazing diamond tools at high temperature，the tool substrates in different heat treatment states are tested and analyzed.Three samples with 0.45% C steel as the substrate of the diamond brazed tool are made.The microstructure and microhardness are measured for the original samples, those heated to 1020℃ in the vacuum ambience and those after brazing with diamond.A comparative analysis is performed among the test data of the three samples.Then the experiment of tensile properties is carried out and the morphology of the fracture surface is observed by using SEM.The results show that the crystalline grain of the substrate becomes larger after heating in the vacuum furnace or brazing，which lead to the great decline of mechanical properties such as strength，hardness and ductility，and serious thermal damage is suffered by the substrate materials.The research results can provide experimental and theoretical guidance for choosing substrate materials and planning brazing process of diamond brazed tools.
Keywords:brazing；diamond tool；substrate；thermal damage