SiCp/6061Al复合材料等离子弧焊工艺参数对焊缝组织及性能的影响

采用等离子弧焊接工艺研究铝基复合材料SiCp/6061Al的焊接性,借助X射线衍射、扫描电镜等手段分析接头组织,着重探讨了在填加和不填加合金化填充材料Ti的情况下,焊接电流、焊接速度对焊缝显微组织及焊接接头力学性能的影响机理,研究表明,在未填加材料Ti时,焊接工艺参数的改变并不能抑制有害相Al4C3的生成,只能改变其尺寸和数量;在填加填充材料Ti时,焊缝熔池中增强相的种类及分布是影响焊接接头性能的主要因素;适当调整焊接工艺参数有利于焊缝中心形成完全以新生颗粒TiC,TiN和AlN为增强相的完全原位反应区;同时减小新旧增强相共存区域的宽度,并消除增强相SiC颗粒的偏聚现象,从而提高了焊接接头的力学性能.     

Ti-Ni合金对SiCp/AlMMCs等离子弧原位焊接焊缝性能的影响

以Ti-Ni合金作为填加材料,采用氮氩混合等离子气对SiCp／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,A1N,Al3Ti和Al3Ni,未发现明显的针状相生成,有效的抑制了脆性相Al4G3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215．4MPa,达到母材强度的67．3％。     

电弧超声对SiC_p/AlMMCs焊缝组织与性能的影响

以Ti合金作为填加材料,以氮氩混合气作为离子气,对SiCp/6061Al基复合材料进行电弧超声等离子弧原位合金化焊接,研究了电弧超声对等离子弧焊接头组织和性能的影响.结果表明,在不加超声时,焊缝中新生AlN相呈细长条状,Al3Ti相粗大,TiC,TiN等新生增强颗粒分布不均匀;在加入超声后,焊缝组织细密,TiC,TiN,AlN等增强相呈细小颗粒状存在,数量增加,且分布均匀,Al3Ti相尺寸减小,数量减少,从而有效改善了焊接接头的组织和性能,使焊接接头抗拉强度最大值达到225MPa,比不加超声时提高了约7%.     

焊接工艺——熔焊

以不同Ti含量的Ti-Al合金作为合金化填加材料,采用氮氲混合等离子气体对SiCp／6061Al复合材料进行等离子弧原位焊接,研究填加材料Ti—Al中Ti质量分数的变化对焊缝组织的影响。结果表明：在熔池凝固过程中,填加材料中Ti质量分数为10％时,可有效抑制有害针状相ALC3的生成;     

焊接工艺——熔焊

以不同Ti含量的Ti-Al合金作为合金化填加材料,采用氮氲混合等离子气体对SiCp／6061Al复合材料进行等离子弧原位焊接,研究填加材料Ti—Al中Ti质量分数的变化对焊缝组织的影响。结果表明：在熔池凝固过程中,填加材料中Ti质量分数为10％时,可有效抑制有害针状相ALC3的生成;     

SiCp/Al基复合材料等离子弧原位焊接研究

采用等离子弧原位焊接工艺研究了SiCp／Al基复合材料的可焊性。结果表明：以Ti为合金化填充材料，以N2＋Ar为离子气，可以大大减弱SiC颗粒与基体Al之间的界面反应。通过拉伸试验、显微硬度测试、金相观察、扫描电镜、X射线衍射分析，对焊接接头进行了研究。得出焊缝表面的蓝黑色薄膜状物质为AlN和Al的混合物，焊缝中心新生相为AlN、TiN和TiC。探讨了接头力学性能不高的原因，并提出了在等离子弧焊条件下提高SiCp／Al焊接接头质量应采取的措施。     

Ti-Ni合金对SiCp/Al MMCs等离子弧原位焊接焊缝性能的影响

以Ti-Ni合金作为填加材料,采用氮氩混合等离子气对SiCp/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,AIN,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215.4MPa,达到母材强度的67.3%.     

焊接工艺/熔焊

采用等离子弧焊接工艺研究铝基复合材料SiCp／6061A1的焊接性，借助x射线衍射、扫描电镜等手段分析接头组织，着重探讨了在填加和不填加合金化填充材料Ti的情况下，焊接电流、焊接速度对焊缝显微组织及焊接接头力学性能的影响机理。研究表明，在未填加材料Ti时，[第一段]     

SiC_p/Al基复合材料等离子弧原位焊接研究

采用等离子弧原位焊接工艺研究了SiCp/Al基复合材料的可焊性。结果表明:以Ti为合金化填充材料,以N2+Ar为离子气,可以大大减弱SiC颗粒与基体Al之间的界面反应。通过拉伸试验、显微硬度测试、金相观察、扫描电镜、X射线衍射分析,对焊接接头进行了研究。得出焊缝表面的蓝黑色薄膜状物质为AlN和Al的混合物,焊缝中心新生相为AlN、TiN和TiC。探讨了接头力学性能不高的原因,并提出了在等离子弧焊条件下提高SiCp/Al焊接接头质量应采取的措施。     

Ti-Al合金对SiCp／6061Al复合材料等离子弧焊焊缝组织的影响

以不同Ti含量的Ti-Al合金作为合金化填加材料,采用氮氩混合等离子气体对SiCp/6061Al复合材料进行等离子弧原位焊接,研究填加材料Ti-Al中Ti质量分数的变化对焊缝组织的影响.结果表明:在熔池凝固过程中,填加材料中Ti质量分数为10%时,可有效抑制有害针状相Al4C3的生成;随填加材料中Ti质量分数的降低,焊缝中未出现脆性相Al4C3,组织中颗粒相的形貌发生较大变化,Al3Ti相的形状由粗大块状变为细长针状,并且数量大为减少;焊缝中其余增强相的尺寸均变得较为细小.     

In-situ weld-alloying plasma arc welding of SiCp/Al MMC

Plasma arc welding was used to join SiCp/ml composite with titanium as alloying filler material. Microstructure of the weld was characterized by an optical microscope. The results show that the harmful needle-like phase Al4C3 is completely eliminated in the weld of SiCp/Al metal matrix composite（MMC） by in-situ weld-alloying/plasma arc welding with titanium as the alloying element. The wetting property between reinforced phase and Al matrix is improved, a stable weld puddle is gotten and a novel composite-material welded joint reinforced by TiN, AlN and TiC is produced. And the tensile-strength and malleability of the welded joints are improved effectively because of the use of titanium.     

Effect of Ti-Al on microstructures and mechanical properties of plasma arc in-situ welded joint of SiCp/Al MMCs

The effect of Ti-Al on microstructures and mechanical properties of SiCp/Al MMC joints produced by plasma arc in-situ weld-alloying was investigated, in which argon-nitrogen mixture was used as plasma gases and Ti-Al alloy as filling composite. The results show that the formation of needle-like harmful phase Al4C3 is effectively prevented in the weld by in-situ weld-alloying/plasma arc welding with Ti-Al alloy sheet filler whose titanium content is more than 20%. The fluidity of molten pool is improved, and stable molten pool is gained for the addition of the Ti-Al alloy. The mechanical properties of welded joint are effectively enhanced by the compact-grain structure and the new reinforced composites such as Al3Ti, TiN, AlN and TiC welded joint. The test results of mechanical property show that the maximum tensile strength of welded joint gained by adding Ti-60Al alloy is up to 235 MPa. The factors influencing the tensile strength were also investigated.     

超声频电弧对SiCp/6061Al等离子弧焊缝微观组织的影响

应用高通滤波器原理设计了一台隔离耦合装置,实现了交流弧焊电源与高频 激励源的隔离与耦合,成功在交流电弧中激励出超声波.以自主研制的A1-5Ti-5Si药芯焊丝为填充材料对SiCp/6061A1基复合材料进行等离子弧原位合金化焊接,在不同频率电弧超声作用下研究了电弧超声频率对焊缝组织的影响.对比0(不加超声),30,40...     

N2在等离子弧原位焊接SiCp/Al基复合材料中的作用

以0．8mm钛片作为填充材料，采用纯氩和氮氩混合等离子气体对SiCp／Al基复合材料进行等离子弧原位焊接，分析加入的N2对焊缝成形、焊缝组织和性能的影响。结果表明，随氮气体积分数增大，焊缝熔深也相应增大：增加氮气还改善了熔池中的热循环状态和冶金反应，生成TiN、AlN等新的增强相，有效地抑制脆性相的生成，改善了焊接接头的性能。力学性能实验表明，采用Ar＋N2作为离子气进行焊接时，焊缝硬度和强度都有提高。当N2体积分数约占15％时，拉伸强度达到最大值233．5MPa。     

Effect of temperature field on types and distribution of reinforcing phases in "in-situ" weld-alloying/PAW of SiCp/6061 Al

Based on theories of heat transfer, physical metallurgy and hydro-mechanical, in order to analyze the effect of welding parameters on species and distribution of reinforcing phases visually and legibly,finite element software ANSYS was used to simulate transient temperature field for SiCp/Al in " in-situ" weld-alloying/plasma arc welding. The results show that the calculated results approximately agreed with the experimental measured results. So the model is basically correct and credible. Based on the numerical solutions and experimental results, effect of temperature field in different welding process parameters( welding current, welding velocity) on species and distribution of reinforcing phases is analyzed. The results show that adjusting and optimizing temperature field appropriately is an effective method to obtain welded joint with better microstructure and property.     

Ti-Si对SiCp/Al基复合材料等离子弧原位焊接性能的影响

以Ti-Si混合粉末作为填充材料,采用氮氩混合等离子气体对SiCp/Al基复合材料进行等离子弧原位焊接,分析SiCp/Al基复合材料的焊接性.结果表明,填充Ti-Si混合粉末进行等离子弧原位焊接时接头组织致密,结合较好,焊缝组织中生成了新的增强颗粒,未发现明显的针状相生成,从而有效地提高了接头的力学性能.力学性能试验表明,采用Ti-Si混合粉末进行等离子弧原位焊接所获得的抗拉强度为232.3MPa.此外探讨了焊接接头中气孔形成的机制以及应采取的相应措施.