5083-H111铝合金轧制板焊接性能及组织研究

随着铝合金轧制板材的广泛应用,轧制板材的焊接性能也成为关注的热点。通过对焊后试样进行拉伸、弯曲和硬度试验以及显微组织观察试验,研究了铝合金5083-H111 (5 mm)轧制板的焊接性能。试验结果表明,确定焊接接头性能良好,满足检验标准要求,且热影响区（HAZ区）不存在明显的软化区,验证5083-H111材质的轧制板材最佳焊接工艺,为生产此类材质产品提供依据。     

焊接间隙对铝合金MIG焊组织性能的影响

文章主要选取6063铝合金挤压板材,采用熔化极惰性气体保护焊MIG进行对接工艺验证试验,通过焊接接头宏观形貌观察、X射线形貌观察、金相显微组织观察和性能分析,了解不同焊接间隙对焊接性能的影响,获得熔化极惰性气体保护焊MIG对母材间隙的要求.结果表明,MIG焊接0.5mm、1.0mm、1.5mm间隙板材焊缝组织性能良好.     

5083铝合金焊接管表面裂纹产生原因分析

5083铝合金具有优良的焊接性能和良好的抗蚀性能,在能源、化工等领域被广泛应用。针对5083铝合金焊接管表面产生裂纹,使用理化检测、扫描电镜、能谱检测、金相显微等技术手段对试样的化学成分、力学性能以及金相组织进行综合分析,发现在试样母材组织和裂纹处存在大量C、Cl、Si、S、O等非金属夹杂。铝合金焊接过程中存在焊接热影响,会导致铝合金焊缝附近存在较大的内应力。结果表明,焊接过程中焊接应力的存在和材料组织中存在大量的非金属夹杂是裂纹产生的根本原因。     

5083铝合金焊接管表面裂纹产生原因分析

5083铝合金具有优良的焊接性能和良好的抗蚀性能,在能源、化工等领域被广泛应用。针对5083铝合金焊接管表面产生裂纹,使用理化检测、扫描电镜、能谱检测、金相显微等技术手段对试样的化学成分、力学性能以及金相组织进行综合分析,发现在试样母材组织和裂纹处存在大量C、Cl、Si、S、O等非金属夹杂。铝合金焊接过程中存在焊接热影响,会导致铝合金焊缝附近存在较大的内应力。结果表明,焊接过程中焊接应力的存在和材料组织中存在大量的非金属夹杂是裂纹产生的根本原因。     

5083铝合金搅拌摩擦焊接头组织及力学性能研究

采用搅拌摩擦焊焊接5083铝合金,光学显微镜OM、透射电镜TEM对焊接接头进行金相分析,拉伸试验和硬度试验对焊接接头力学性能进行分析.结果表明,焊接接头焊核区为晶粒细小的等轴晶组织,热力影响区晶粒细小且沿剪切方向拉长,热影响区晶粒明显长大.其接头的力学性能显著优于传统的熔化焊,抗拉强度约为母材的90％,塑性与母材相当;...     

5083铝-镁合金MIG焊焊接分析

本文主要介绍了5083铝-镁合金的焊接的方法及采用脉冲MIG焊进行5083铝一镁合金焊接工艺试验研究的情况。介绍了焊接铝合金的主要规范参数和工艺控制要点，并对焊接过程中易出现的焊接缺陷进行了分析，提出了消除焊接缺陷的方法和措施。并针对MIG气体保护焊实际操作的特点，提出了教学培训中应注意的要点。     

焊接材料对7075铝合金焊接性能及组织的影响探讨

为探究焊接材料对7075铝合金焊接性能及焊缝组织的影响,采用全自动MIG焊焊接方式就ER4043和ER5356两种焊丝焊接7075铝合金后的焊接接头形貌、焊接接头力学性能、焊接组织进行观察.试验结果发现,ER5356焊丝在焊接形貌上,拉伸性能、塑性性能、接头硬度三个接头力学性能以及纤维组织强度上都更加优良,整体焊接性能...     

搅拌摩擦加工参数对5083铝合金组织性能的影响

采用搅拌摩擦加工方法对不同焊接参数下的退火态5083铝合金的组织和性能进行研究.通过显微硬度实验研究了硬度在前进侧和后退侧以及加工区上下部分的分布规律;通过金相观察研究了加工区表面带状纹理和腐蚀后观察到的弧纹之间的关系.对母材和加工区用扫描电镜观察了析出相的形貌、尺寸及分布规律.结果表明:高硬度区宽度随着轴肩直径的增大而增大,随着转速和焊速之比(ω/ν)的增加而增大,硬度在前进侧(AS)和后退侧(RS)的分布是不均匀的;从母材到加工区硬度逐渐上升,RS侧的上升速度约为AS侧的一半.     

工艺流程对船用5083合金挤压型材性能的影响

为优化5083铝合金挤压型材的生产工艺,对拉伸变形及退火处理后的5083铝合金型材的力学性能及腐蚀性能进行了研究。结果表明,拉伸强化可以有效提升试样强度;完全退火降低了试样强度,提高了试样韧性;低温退火降低试样强度的同时还大幅降低了试样的抗腐蚀性能。考虑到成本因素优先考虑挤压+拉伸强化工艺流程,对于某些需要特定成型的船舶构件,也可考虑采用挤压+完全退火+拉伸强化的工艺流程。     

轴肩直径对5083铝合金FSW接头腐蚀行为和力学性能的影响

对厚度为5 mm的5083铝合金板材进行单面对接搅拌摩擦焊接（FSW）,研究了不同轴肩直径（12,14和16 mm）对搅拌摩擦焊接头金相组织、耐蚀性能以及力学性能的影响。结果表明：随着轴肩直径的增加,焊核区晶粒尺寸逐渐增大,第二相尺寸也有所增加,且出现了不同程度的聚集,热机影响区晶粒尺寸的均匀性变差。从热影响区到焊缝中心,电极电位逐渐增加,焊核区的表面膜一直处于此消彼长的稳定状态,而热机影响区和热影响区的表面膜以溶解破裂为主。焊接接头的表层硬度曲线呈“W”型分布,硬度最低值出现在前进侧热影响区上。当搅拌头轴肩直径为14 mm时,焊核区晶粒尺寸细小,第二相尺寸均匀,接头表面的钝化区间较宽,腐蚀电流密度最小,表面膜稳定,耐蚀性能最好。对应接头的抗拉强度为288 MPa,断后伸长率为10.6%,焊接接头系数达到89.6%,接头的塑性和强度均达到最大值。     

The effect of loading mode on the stress-corrosion cracking of aluminum alloy 5083

Recent studies have revealed that the mechanism of stress-corrosion cracking (SCC) of high-strength Al-Zn-Mg alloys involves both dissolution and hydrogen embrittlement (HE); moreover, under tensile-loading conditions, evidence exists that the hydrogen mechanism is dominant. In the present study, the role of HE in the SCC of Al-Mg alloys was investigated using commercial Al-4.4 wt pct Mg alloy, 5083. The susceptibility of this alloy to SCC in a saline environment was evaluated in Mode I (tension) and Mode III (torsion), using precracked fracture toughness specimens. The greater susceptibility found in Mode I indicates that HE is involved in SCC. As further evidence that HE is operating, susceptibility increased when As, a hydrogen recombination inhibitor, was added to the test solution under Mode I conditions. Issues related to the overall validity of the loading mode experiment are also addressed.     

Development of a low-melting-point filler metal for brazing aluminum alloys

The study is concerned with developing low-melting-point filler metals for brazing aluminum alloys. For this purpose, thermal analyses of a series of Al-Si-Cu-Sn filler metals have been conducted and corresponding microstructures observed. The results showed that the liquidus temperature of Al-Si-Cu filler metals dropped from 593 °C to 534 °C, when the amount of copper was increased from 0 to 30 pct. As the copper content reached further to 40 pct, the liquidus temperature would rise to 572 °C. By adding 2 pct tin into the Al-Si-20Cu alloys, the liquidus and solidus temperature would fall from 543 °C to 526 °C and from 524 °C to 504 °C, respectively. The main microstructures of Al-Si-Cu alloys consist of the α-Al solid solution, silicon particles, the CuAl₂ (ϑ) intermetallic, and the eutectic structures of Al-Si, Al-Cu, and Al-Si-Cu. For further improvement of the brazability of this filler metal, magnesium was added as a wetting agent, which would remove the residual oxygen and moisture from the brazed aluminum surface and reduce the oxide film. Based on results gleaned from the thermal analyses, a new filler metal with the composition Al-7Si-20Cu-2Sn-1Mg is proposed, which possesses a melting temperature range of 501 °C to 522 °C and a microstructure that includes an Al-Si solid solution, silicon particles, a tin-rich phase, and CuAl₂, CuMgAl₂, and Mg₂Si intermetallic compounds. When this filler metal was used to braze the 6061-T6 aluminum alloy, an optimized bonding strength of 196 ± 19 MPa was achieved.     

Stress-corrosion cracking susceptibility of the superplastically formed 5083 aluminum alloy in 3.5 pct NaCl solution

The slow strain rate test (SSRT) method was employed to study the stress corrosion cracking (SCC) susceptibility of the superplastic 5083 Al alloy in a 3.5 pct NaCl solution after superplastic forming and various heat treatments. Experimental results showed that both superplastically formed specimens and specimens subject to the same thermal processes as that used in superplastic forming suffered severe SCC susceptibility, and obvious intergranular fracture surfaces were also observed. Furthermore, scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDS) analyses demonstrated that the thermal processes of superplastic forming led to continuously distributed precipitation layers of β phase (Mg₂Al₃) at grain boundaries, i.e., sensitization had occurred. However, postforming annealing treatment at 345 °C for 1 hour eliminated the sensitization effect of both specimens. In this case, the SCC susceptibility was alleviated, and the fracture surfaces changed to a transgranular dimpled structure, characteristic of that found in the as-received specimen. From the metallographic observations, it was also seen that a number of cavities appeared at the grain boundaries of the superplastically formed specimen. However, the cavitation effect on SCC susceptibility is minor in comparison with the sensitization effect.     

Structure and phase composition of composite pellets based on the ALTEK heat-resistance aluminum alloy with boron-containing filler

Composite pellets based on the ALTEK heat-resistant aluminum alloy (Al-Cu-Mn-Zr system) and reinforced with B₄C particles in a volume fraction of ～11% and 1–10 μm in size are produced by mechanical alloying. The pellet structure includes a significant amount of inclusions of the Al₁₅(Fe, Mn)₃Si₂ phase, which have a globular shape and an average size of about 2 μm. It is suggested that both the inclusions and B₄C can be considered a reinforcing filler.     

Bulk nanocrystalline aluminum 5083 alloy fabricated by a novel technique: Cryomilling and spark plasma sintering

Dense, bulk nanocrystalline aluminum 5083 alloy was fabricatedvia a combined technique: cryomilling (mechanical milling at cryogenic temperature) to achieve the nanocrystalline Al 5083 powder and spark plasma sintering (SPS) to consolidate the cryomilled powder. The results of X-ray diffraction analysis indicate that the average grain size in the SPS consolidated material is 51 nm, one of the smallest grain sizes ever reported in bulk Al alloys produced by powder metallurgy derived methods. In contrast, transmission electron microscopy (TEM) analysis revealed a bimodal grain size distribution, with an average grain size of 47 nm in the fine-grained regions and approximately 300 nm in the coarse-grained regions. Nanoindentation was used to evaluate the mechanical properties and the uniformity of the consolidated nanocrystalline Al 5083. The hardness of the material is greatly improved over that of the conventional equivalent, due to the fine grain size. The mechanisms for spark plasma sintering and the microstructural evolution are discussed on the basis of the experimental findings.     

铝对复杂黄铜组织及性能的影响

用光学显微镜(OM)、硬度(HV)和万能试验机对添加不同铝含量(1.5%、2.0%、2.5%、3.0%、3.5%)的复杂黄铜(Cu-22.7Zn-Al-1.0Ni)组织与性能进行了研究.研究结果显示,铝能使合金α相区显著缩小、β相区增加,并起到细化α相、β相的作用,提高合金的抗拉强度、硬度.合金的机械性能随铝含量增加,其抗拉强度和屈服强度提高,而延伸率和冲击韧性下降,当铝含量为3.0%时,0.2 mm Y态板材硬度达到255 HV、抗拉强度达到820 MPa.     

胶接对Al-Li-S4铝合金织构的影响

将新一代Al-Li-S-4铝锂合金用砂纸打磨,用磷酸进行阳极化处理,用环氧320/322胶胶接,然后以12℃/min的速率升温至120℃,保温固化1 h。采用BrukerD8 Discover型X射线衍射仪测定胶接固化后的织构,并与未胶接的Al-Li-S-4合金进行比较。结果表明:胶接后合金主要织构的成分没有发生大的变化,但在胶接应力的作用下织构的位置发生变化。其中,黄铜织构与铜织构较稳定,而立方织构的取向密度变化较大,位置也有所改变。通过研究胶接对材料织构的影响,了解材料内部应力及晶粒取向上的变化,为胶接工艺的制定及改进提供参考。