Study on diffusion welding parameters of particle-reinforced aluminium matrix composite Al2O3p/6061Al

１．ＩｎｔｒｏｄｕｃｔｉｏｎＡｌｕｍｎｉｕｍｍａｔｒｉｘｃｏｍｐｏｓｉｔｅ,ｄｕｅｔｏｉｔｓｅｘｃｅｌｌｅｎｔｃｏｍｐｒｅｈｅｎｓｉｖｅｐｒｏｐｅｒｔｉｅｓｓｕｃｈａｓｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈ,ｈｉｇｈｓｐｅｃｉｆｉｃｍｏｄｕｌｅ,ｒｅｓｉｓｔａｎｃｅｔｏｅｌｅｖａｔｅｄｔｅｍｐｅｒａｔｕｒｅ,ｒｅｓｉｓｔａｎｃｅｔｏｒａｄｉａｔｉｏｎａｎｄｇｏｏｄｄｉｍｅｎｓｉｏｎａｌｓｔａｂｉｌｉｔｙ,ｈａｓａｔｔｒａｃｔｅｄｇｒｅａｔａｔｔｅｎｔｉｏｎｆｒｏｍｍａｔｅｒｉａｌｓｃｉｅ…     

Study on behavior of reinforcement in molten pool for submicron composite Al_2O_3p/6061 Al during laser welding

0ＩｎｔｒｏｄｕｃｔｉｏｎＡｌｕｍｉｎｕｍｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓｈａｖｅｍａｎｙｏｕｔｓｔａｎｄｉｎｇｐｒｏｐｅｒｔｉｅｓ,ｓｕｃｈａｓｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈ ,ｈｉｇｈｓｐｅｃｉｆｉｃｍｏｄｕｌｕｓ,ｅｌｅｖａｔｅｄｔｅｍｐｅｒａｔｕｒｅｐｒｏｐｅｒｔｉｅｓ ,ｇｏｏｄｒａｄｉａｔｉｏｎｒｅｓｉｓｔａｎｃｅａｎｄｓｉｚｅｓｔａｂｉｌｉｔｙ ,ｓｏｔｈｅｙｈａｖｅａｔｔｒａｃｔｅｄｍｕｃｈａｔｔｅｎｔｉｏｎｆｒｏｍｍａｔｅｒｉａｌｓｃｉｅｎｔｉｓｔｓ.Ｂｙｒｅｐｌａｃｉｎｇｇｒ…     

Relaxation of residual stresses in 20%SiC_w/6061Al composite as-extruded at high temperature

1　ＩＮＴＲＯＤＵＣＴＩＯＮＡｌｕｍｉｎｕｍｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｒｅｉｎｆｏｒｃｅｄｗｉｔｈｓｉｌｉ ｃｏｎｃａｒｂｉｄｅｗｈｉｓｋｅｒ (ＳｉＣｗ/Ａｌ)ａｓａｎｅｗｔｙｐｅｏｆｓｔｒｕｃｔｕｒａｌｍａｔｅｒｉａｌｎｏｔｏｎｌｙｈａｓｃｅｒｔａｉｎａｄｖａｎｔａｇｅｓｓｕｃｈａｓｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈ ,ｈｉｇｈｓｐｅｃｉｆｉｃｍｏｄｕｌｕｓ ,ｌｏｗｃｏｅｆｆｉｃｉｅｎｔｏｆｔｈｅｒｍａｌｅｘｐａｎｓｉｏｎ (ＣＴＥ)ａｎｄｓｏｏｎ ,ｂｕｔａｌｓｏｃａｎｂｅｓｅｃｏｎｄａｒｉ…     

Elastic modulus of SiC_w/6061Al alloy composites as-squeeze-cast

1　ＩＮＴＲＯＤＵＣＴＩＯＮＣｏｍｐｏｓｉｔｅｏｆｓｉｌｉｃｏｎｃａｒｂｉｄｅｗｈｉｓｋｅｒｒｅｉｎｆｏｒｃｅｄａｌｕｍｉｎｕｍ (ＳｉＣｗ/Ａｌ)ａｓａｎｅｗｔｙｐｅｏｆｓｔｒｕｃｔｕｒａｌｍａ ｔｅｒｉａｌｎｏｔｏｎｌｙｈａｓｓｏｍｅａｄｖａｎｔａｇｅｓｓｕｃｈａｓｈｉｇｈｓｐｅ ｃｉｆｉｃｓｔｒｅｎｇｔｈ ,ｈｉｇｈｓｐｅｃｉｆｉｃｍｏｄｕｌｕｓ ,ｌｏｗｔｈｅｒｍａｌｃｏ ｅｆｆｉｃｉｅｎｔｏｆｅｘｐａｎｓｉｏｎａｎｄｓｏｏｎ[1,2 ] ,ｂｕｔａｌｓｏｃａｎｂｅｓｅｃｏｎｄａｒｉｌｙｓｈａｐｅｄｂｙｔｈ…     

Interface reaction in aluminium matrix composite at laser welding

1　ＩＮＴＲＯＤＵＣＴＩＯＮＡｌｕｍｉｎｕｍｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓｈａｖｅｍａｎｙｏｕｔ ｓｔａｎｄｉｎｇｐｒｏｐｅｒｔｉｅｓ ,ｓｕｃｈａｓｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈ ,ｓｐｅｃｉｆｉｃｍｏｄｕｌｕｓ ,ｅｌｅｖａｔｅｄｔｅｍｐｅｒａｔｕｒｅ ｐｒｏｐｅｒｔｉｅｓ ,ｒａｄｉａｔｉｏｎｒｅｓｉｓｔａｎｃｅａｎｄｓｉｚｅｓｔａｂｉｌｉｔｙ ,ｓｏｔｈｅｙｈａｖｅａｔ ｔｒａｃｔｅｄｇｒｅａｔａｔｔｅｎｔｉｏｎｓｆｒｏｍｍａｔｅｒｉａｌｓｃｉｅｎｔｉｓｔｓ .Ｂｙｒｅｐｌａｃｉｎｇｇｒａｄ…     

Predicting effects of diffusion welding parameters on welded joint properties by artificial neural network

1　ＩＮＴＲＯＤＵＣＴＩＯＮＭｅｔａｌｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓ (ＭＭＣｓ) ,ｄｕｅｔｏｔｈｅｉｒｏｕｔｓｔａｎｄｉｎｇｐｒｏｐｅｒｔｉｅｓｓｕｃｈａｓｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈ ,ｓｐｅｃｉｆｉｃｍｏｄｕｌｕｓ ,ｓｉｚｅｓｔａｂｉｌｉｔｙ ,ｈｉｇｈ ｔｅｍｐｅｒａｔｕｒｅ ｒｅｓｉｓｔａｎｔａｎｄｃｏｓｍｉｃ ｒａｙｒｅｓｉｓｔａｎｔ ,ａｒｅｗｉｄｅｌｙｕｓｅｄｉｎａｅｒｏｓｐａｃｅ ,ａｖｉａｔｉｏｎａｎｄｅｌｅｃｔｒｏｎｆｉｅｌｄｓ ,ａｎｄｂｅｃｏｍｅｔｈｅｍａｊｏｒｄｅｖｅｌ…     

Investigation on Behavior of Rare Earth Element Cerium in Aluminum-Lithium Alloys by Internal Friction Method

1 ＩｎｔｒｏｄｕｃｔｉｏｎＡｌｕｍｉｎｉｕｍ ｌｉｔｈｉｕｍａｌｌｏｙｓａｒｅｂｅｉｎｇｄｅｖｅｌｏｐｅｄａｓａｄｖａｎｃｅｄｓｔｒｕｃｔｕｒａｌｍａｔｅｒｉａｌｓｆｏｒａｅｒｏｓｐａｃｅｔｅｃｈｎｏｌｏｇｙｏｗｉｎｇｔｏｔｈｅｉｒｌｏｗｄｅｎｓｉｔｙ ,ｈｉｇｈｓｔｒｅｎｇｔｈａｎｄｓｐｅｃｉｆｉｃｒｉｇｉｄｉｔｙｃｏｍｐａｒｅｄｗｉｔｈｃｏｎｖｅｎｔｉｏｎａｌａｌｕｍｉｎｕｍａｌ ｌｏｙｓ ,ｂｕｔｔｈｅｒｅｓｔｉｌｌｅｘｉｓｔｓｏｍｅｄｉｓａｄｖａｎ ｔａｇｅｓ ,ｓｕｃｈａｓｌｏｗｐｌａｓｔｉｃ…     

STUDIES ON MICROYIELD BEHAVIOR OF A SiC p/2024Al COMPOSITE

１ＩＮＴＲＯＤＵＣＴＩＯＮＤｕｅｔｏｔｈｅｅｘｃｅｌｅｎｔｃｏｍｐｒｅｈｅｎｓｉｖｅｐｒｏｐｅｒｔｉｅｓｓｕｃｈａｓｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈａｎｄＹｏｕｎｇ’ｓｍｏｄｕｌｕｓ,ｌｏｗｅｒｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙａｎｄｔ...     

Interface and microstructure characteristics of SiC_p/2024 aluminium alloy composite

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｉｍｐｏｒｔａｎｃｅｏｆｐａｒｔｉｃｕｌａｔｅｒｅｉｎｆｏｒｃｅｄｍｅｔａｌｍａｔｒｉｘｃｏｍｐｏｓｉｔｅｓ(ＰＭＭＣｓ)ｄｕｅｔｏｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈ ,ｈｉｇｈｓｐｅｃｉｆｉｃｍｏｄｕｌｕｓ ,ｂｅｔｔｅｒｒｅｓｉｓｔａｎｃｅｔｏｗｅａｒａｎｄｔｈｅｒｍａｌｓｔｅａｄｉｎｅｓｓｈａｓａｔｔｒａｃｔｅｄｍｕｃｈｉｎｔｅｒｅｓｔｉｎｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｔｈｅｍａｎｕｆａｃｔｕｒｉｎｇｐｒｏｃｅｓｓｆｏｒｓｕｃｈｃｏｍｐｏｓｉｔｅｓ .Ｔｈ…     

Mechanical properties of rapidly solidified Al-Ti alloys after thermal exposure

1　ＩＮＴＲＯＤＵＣＴＩＯＮＡｌｕｍｉｎｉｕｍａｌｌｏｙｓｒｅｉｎｆｏｒｃｅｄｗｉｔｈａｌｕｍｉｎｉｄｅｐａｒ ｔｉｃｌｅｓ (ＮｉＡｌ3,ＦｅＡｌ3,ＺｒＡｌ3,ＴｉＡｌ3,ｅｔｃ) ｐｏｓｓｅｓｓｈｉｇｈｓｐｅｃｉｆｉｃｓｔｒｅｎｇｔｈ ,ｈｉｇｈｓｐｅｃｉｆｉｃｍｏｄｕｌｕｓａｎｄｅｘ ｃｅｌｌｅｎｔｐｒｏｐｅｒｔｉｅｓｂｏｔｈａｔａｍｂｉｅｎｔａｎｄｅｌｅｖａｔｅｄｔｅｍ ｐｅｒａｔｕｒｅ[1～ 6 ] .Ｃｏｍｐａｒｅｄｗｉｔｈｍｏｓｔｏｔｈｅｒａｌｕｍｉｎｉｕｍ ｒｉｃｈｉｎｔｅｒｍｅｔａｌｌｉｃ ,Ａｌ3Ｔｉｉ…     

Microstructures of electron beam welding joint of CNTs/ Al composites

Carbon nanotube(CNT) reinforced aluminum metal matrix composites were welded by electron beam welding and the microstructures of welded joints were investigated.The result showed that the interfacial reaction happened between the CNTs and Al matrix,which resulted in producing brittle Al4C3 compounds in electron beam welds.The extent of interfacial reaction varies gradually in the depth and width direction.The length of the reactants Al4C3 became short duo to the temperature gradient in the molten pool.The quantity and size of Al4C3 compounds increased with the increase of beam current and the decrease of welding speed in the middle zone of weld.However,no needle-like phase Al4C3was observed in HAZ.     

Joining process and strength in PVC friction stir spot welding with fabricating composite material at welding area*

In order to improve the strength of FSSWed PVC joints, SiC particles were compounded into the welded region at the same time as the welding process. The joining process and its effect on strength of FSSWed PVC joints were investigated in a joining experiment with a PVC plate having a different guide hole diameter for filling the SiC particles. In the case of the specimen compounded with SiC particles with guide hole diameter of 8 mm, SiC particles could be dispersed uniformly in the welded area. In the specimens with guide hole diameters of 5 and 2 mm, dispersion of SiC particles was not observed inside of the welded area. Degradation and increase in local mechanical property was significantly observed at edge of the keyhole and inside the welded area, respectively, in the specimen with a guide hole diameter of 8 mm. The width of welded area increased with increasing guide hole diameter. The joining strength was improved by fabricating composite material in the welded region. The strength increased with increasing guide hole diameter. It is considered that joining strength was significantly affected by the width of the welded area. According to temperature distribution and observation of material flow using a high speed camera, contact between the welding tool and SiC particles before plunging into a lower sheet induced increasing heat input during the process and resulted in promoting the friction stirring. Therefore, it is considered that change in guide hole diameter leads to change in contact area between welding tool and SiC particles and also change in width of the welding area resulting in change in the joining strength.     

Al/316L爆炸复合双金属板界面结构分析

以316L板为基、铝板为覆材进行爆炸焊接,利用扫描电子显微镜及能谱仪研究了爆炸焊接双金属板界面组织结构并用纤维硬度计测量了界面处硬度.结果表明,界面中间灰色区域,以化合物的形式分布在界面上,宽度5～20μm,区域中和边缘铝量有所变化;焊缝区的硬度值较基体316L板及铝板各自的硬度值高,表明界面有化合物存在.     

SiCp/LY12复合材料的电阻点焊工艺研究

对SiCp/LY12铝基复合材料电阻点焊焊接工艺参数进行了优化,并对接头微观组织和性能进行了分析,结果表明:接头质量良好,在焊缝中心区域没有发现针状析出物即没有发生界面反应,焊接气孔及裂纹缺陷也极少,但在焊缝出现了SiC颗粒偏聚现象.总的来说,用电阻点焊来焊接SiCp/LY12铝基复合材料是可行的.     

铝合金电子束焊接熔透特征量的确定

基于视觉图像传感方法,通过设计的平板和斜板试验,对铝合金电子束焊接熔透特征量的提取进行了研究.结果表明,铝合金电子束焊接过程中熔深状态从未熔透向熔透转变时,特征区域宽(W)有相应的响应,特征区域后长(RL)无明显反应;经分析W作为熔透特征量,可用于监测焊接熔深状态的突变,为解决铝合金电子束焊接熔透控制提供了一种有效的途径.     

铝合金激光-电弧双面焊接头特征分析

采用激光-电弧双面焊工艺进行铝合金焊接试验，发现该工艺不仅可以获得稳定可靠的焊接过程与美观的焊缝成形，还可以有效地增加接头熔深和降低焊接成本。主要研究了焊接参数对双面焊接头特征的影响。结果表明，激光功率增加时，双面焊两侧的熔宽都以同样的趋势增大；焊接电流增大时，电弧侧熔宽的增加趋势明显大于激光侧；增加激光功率或提高焊接电流都会引起焊缝最小熔宽的增大，且焊缝最小熔宽的深度也发生一定的变化。随焊接速度的提高，激光侧的深宽比增加，而电弧侧的深宽比减小。     

镀Zn钢-6016铝合金异种金属的激光熔钎焊及数值模拟

熔钎焊是抑制或减少钢/铝异种金属激光焊接过程中FeAl脆性金属间化合物产生的有效工艺方法。采用光纤激光器,不添加任何钎料,对1.2 mm厚DC56D+ZF镀锌钢和6016铝合金平板试件进行激光搭接焊试验,利用MATLAB软件,针对焊接过程的实际情况,在一定的基本假设下建立准稳态下钢/铝异种金属激光焊接熔池形状的数学模型,基于准稳态形状控制方程数值计算获得的熔池几何形状分布,结合试验来调整焊接工艺参数,获得最佳焊接成形,利用卧式金相显微镜、扫描电镜和X射线衍射仪等手段研究焊接接头各区域的金相组织、主要元素分布与物相组成。结果表明:焊接激光束照射搭接在钢板上的铝板对接焊缝时,焊接功率和焊接速度对熔池几何形状的影响较大,随着激光功率的增大,熔深增加;而随着焊接速度的增加,熔深却变浅。当焊接功率为1 600~1 800 W、焊接速度v=30 mm/s、离焦量D=0 mm时,焊缝成形性良好,无明显裂纹、气孔等缺陷,焊接接头区域存在一个台阶状结构,在平台区域,钢/铝两钟金属存在明显的界限,界面结合依靠液态的铝在钢母材表面上的润湿、填充和铺展等作用;下凹区域,钢/铝熔合较好,Fe和Al元素的混合区宽度较大,未形成明显的FeAl脆性金属间化合物,Fe和Al的热扩散是该区域界面结合的主要原因。     

Laser melt injection in aluminum alloys: on the role of the oxide skin

In this paper the method of laser melt injection of SiC particles into an aluminum substrate is investigated both experimentally and theoretically. An extremely small operational parameter window was found for successful injection processing. It is shown that the final injection depth of the particles is controlled mainly by the temperature of the melt pool rather than by the particle velocity. A theoretical model that takes into account the wetting behavior and the particle penetration processes is developed on the basis of the observed particle velocity, thickness and area fraction of oxide skin that partially covers the surface of the heated aluminum melt pool. The model reveals the role of the oxide skin: it is relatively strong at low temperature and acts as a severe barrier for the injection process. It was found that preheating the aluminum substrate results in a higher temperature of the melt pool and partial dissolution of the oxide skin, through which the injected particles are able to penetrate.     

激光焊接条件下20%SiCw/6061铝基复合材料焊缝特性分析

在激光焊接条件下，分析丁20％SiCw／6061铝基复合材料焊缝表面及内部特性，指出在激光焊接条件下，铝基复合材料的焊缝较窄、深宽比大；焊缝可分为焊缝中心焊接区、熔化区及来变化区三部分；在中心焊接区内有大量Al4C3生成，造成焊缝较脆，窖易断裂。     

铝合金激光立焊特性分析

以4 mm厚5A06铝合金为研究对象,利用3 kW的CO2激光器进行激光立焊和平焊工艺试验,对铝合金激光立焊的焊缝成形和气孔特征进行研究.结果表明,立焊的正面下凹量和背面下塌量均小于平焊,随着焊接热输入的增加,立焊和平焊的差异增大.立焊与平焊的焊缝成形和接头尺寸略有差异,当热输入较大时,立焊的正反面熔宽略小于平焊,而熔深则略大于平焊.铝合金激光立焊的气孔多以体积较大且形状不规则的气孔或孔洞组成,从气孔分布位置和形状看,立焊与平焊的差别不大,气孔多分布在焊缝中部且尺寸较大,相同工艺条件下,立焊的气孔数量略低于平焊.