Ti-Ni合金对SiCp/AlMMCs等离子弧原位焊接焊缝性能的影响

Effects of Ti-Ni on properties of plasma arc "in-situ" welding for SiCp/Al MMCs

关键词:  SiC_p/Al基复合材料  等离子弧  原位焊接  Ti-Ni合金

Key words:  SiC_p/Al MMCs  plasma arc  "in-situ" welding  Ti-Ni alloy

摘要:

以Ti-Ni合金作为填加材料,采用氮氩混合等离子气对SiC_p/Al基复合材料进行等离子弧原位焊接。结果表明,填加Ti-Ni合金进行等离子弧原位焊接,在焊缝组织中生成了新的增强颗粒TiN,TiC,AlN,Al₃Ti和Al₃Ni,未发现明显的针状相生成,有效的抑制了脆性相Al₄C₃,并且接头组织致密,结合较好。Ni元素的添加,降低了SiC溶解程度,使得熔池中的结晶热显著提高,改善了熔池的流动性。同时在焊缝组织中形成了新的增强相AlNi,Al₃Ni,从而有效地提高接头的力学性能。采用Ti-Ni合金进行等离子弧原位焊接,接头的抗拉强度为215.4 MPa,达到母材强度的67.3%。

Abstract:

Plasma arc "in-situ" welding of SiC_p/Al MMCs were carried out using argon-nitrogen mixture as plasma gases with Ti-Ni alloying as "in-situ" material.The results showed that the new composite reinforced phases are produced in the seam, such as TiN, TiC, AlN, Al₃T, Al₃Ni, which ensured the quality of joints, but the needle-like brittle phases Al₄C₃ is not found, the metal Ni reduced the solubility of SiC, and increased the crystallization heat greatly, which improved the fluidity of weld pool.The new reinforced phases like AlNi, Al₃Ni improve the mechanical properties of weld seam effectilvely.The mechanical testing results showed that the maximum tensile strengths obtained with Ti-Ni alloy as "in-situ" material are 215.4 MPa, which is about 67.3% of the base metal stength.