Mn元素对CuZnNi钎料润湿性及钎焊接头组织和性能的影响

打开文本图片集

Abstract： Element Mn with different contents were added into CuZnNi brazing filler metals，and the melting point， wettability and microstructure composition of CuZnNiMn brazing filler metals were studied. Subsequently， the CuZnNiMn brazing filler metal was used to induction braze YG8 hard alloy and Q235 steel and the effect of diferent Mn contents on the microstructure composition and tensile strength of the brazed joint were discussed.The results showed that with the increase of Mn content （wt.） from 0% to 6% ，theliquid phaselinesofCuZnNiMn brazing filler metal decreased from 1014.45∘C to 915.88∘C ，so that the wettability of the brazing filler metal improved.The wetting and spreading area of CuZnNiMn brazing filer metal on the steel surface increased from 210mm2 to 310mm2 . The microstructure of CuZnNiMn brazing filler metal was mainly composed of gray-white （20号 a -Cu solid solution and dark gray β 0 [β′） Cu-Zn solid solution. The increase of Mn content in the solder changed the proportion and morphology of the two phases in the structure. When the Mn content increased to 6% ， the two kinds of phase generated segregation.The induction brazed joint between YG8 hard aloy and Q235 steel was mainly composed of Co-Cu-Ni solid solution in the interface of brazing seam and YG8 hard alloy，also a -Cu solid solution and Cu-Zn alloy in thebrazing seam center. With the increase of Mncontent in the solder，the tensile strength of the brazed joint increased first and then decreased with the Mn content increasing.When the Mn content was 4% ，the tensile strength of the brazed joint reached the maximum value of 325MPa

Keywords： Mn element; CuZnNiMn brazing filler metal; weting and spreading; microstructure; tensile strength

1 序言

YG8硬质合金因含有 8%C⋅ 粘结相，在保持较高韧性的同时，兼具高硬度、高耐磨性、良好的抗冲击性及热稳定性，广泛应用于矿山钻头、耐磨部件、冷作模具、拉拔模及特定切削刀具等领域[1-3]。（剩余9458字）