10 mm厚LF2铝合金搅拌摩擦焊温度分布及组织分析

采用嵌入热电偶测温法得到了10mm厚LF2铝合金搅拌摩擦对焊时不同深度（2、5和8mm）、距离搅拌针不同位置的FSW温度分布；通过对焊缝不同位置的金相观察。分析了温度场对10mm LF2搅拌摩擦焊焊缝金属组织的影响。实验结果表明，返回侧温度略高于前进侧，但最大不超过40℃；焊缝顶部的最高温度出现在与轴肩接触的边缘区域，而焊缝底部的最高温度出现在搅拌针边缘；同时焊缝底部出现的“鼓”形组织表明焊缝不同深度的温度分布不仅与热源产热量有关，还与材料的流动情况有关。     

搅拌摩擦焊缝中的洋葱环形成分析

研究了搅拌摩擦焊焊接铜合金、铝合金时接头中出现的洋葱环结构,分析其形成及影响因素。结果表明:洋葱环的实质是搅拌针旋转前进时其带动的软化层与上一软化层塑性金属间相对移动摩擦叠加后产生的一种轨迹;由于搅拌针区域摩擦热输入不足,层间新生成的晶核呈弥散分布,层间与层内晶粒形状不同,从宏观上看,接头纵剖面上形成了结构重叠的半圆环结构,而从横剖面上就形成了独特的“洋葱环”结构;焊缝中心纵剖面上出现环间距大小与搅拌针旋转一周向前移动的距离基本相等。     

Plastic flow pattern and its effect in friction stir welding of A2024 and A1060

During the friction stir welding （FSW）, the property of the welding joint is highly affected by the plastic and viscous flow behavior of the softened material. The flow pattern of the welded material was examined through observing the microstructural distribution of friction stir welded joints between dissimilar 2024 and 1060 aluminum alloy. The experimental results show that the flow patterns of material at different locations in the weld are different and can be divided into four layers along the thickness direction： surface flow layer influenced by the shoulder of the tool, in which the material tends to flow as integrity; horizontal flow layer influenced by the surface flow layer, in which the material of surface flow layer enters and flows forwards under the advancing force of the tool; vertical flow layer （plastic flow area induced by stirring of the pin）, in which the flow pattern is complex and onion rings can often be observed; unstirred bottom layer because of the length of the pin being shorter than the thickness of the plates. The effeet of plastic flow on welding quality was further investigated. The study suggests that welding quantity is significantly influenced by the flow pattern and defects always appear in horizontally lamellar flow region because of the complex flow pattern.     

LY12搅拌摩擦焊焊缝成型及接头微观组织分析

利用MEF3光学显微镜和JSM-6700F场发射扫描电镜分析不同焊接参数下焊缝成型特点及无缺陷致密焊接接头的微观组织变化。研究表明:对厚6mmLY12合金,当焊接速度在20mm/min时,搅拌头旋转速度在1200～900r/min间变化时焊缝致密无缺陷,其焊核区晶粒从上表面到下表面逐渐减小;等轴晶粒出现在搅拌头尺寸范围内,在搅拌头尺寸边缘地带,突然出现具有一定流向的受拉变形的晶粒带;接近轴肩的末端区域有热量输入,晶粒开始长大。     

黄铜H62搅拌摩擦焊接头的微观组织及性能

针对H62黄铜进行搅拌摩擦焊实验研究,初步分析工艺参数对接头的组织及力学性能的影响。结果表明:当焊接速度与搅拌头旋转速度的比值保持在0.09~0.15之间,压入深度在0.1~0.2 mm之间时,可得到组织致密、无孔洞的搅拌摩擦焊接头;用搅拌摩擦焊得到的黄铜接头的力学性能比母材低,但比熔化焊得到的接头性能要高,其平均抗拉强度可达到母材的88%。     

锅炉水冷炉排弯曲问题的探讨

介绍了水冷炉排结构及产生弯曲变形的原因,提出了解决的对策.     

铝合金搅拌摩擦焊焊接缺陷分析

采用搅拌摩擦焊方法对6mm厚的2A12及3A21铝合金进行焊接。对其焊接速度、旋转速度及压入量等工艺参数选择不当所产生的接头缺陷进行了分析；焊接缺陷的产生与焊接热输入及焊缝塑性金属的软化相关。当热输入不足或者塑性金属的软化程度较差时都会导致焊接缺陷的形成。     

Microstructures and properties analysis of dissimilar metal joint in the friction stir welded copper to aluminum alloy

This paper mainly concentrated on the feasibility of friction stir welding of dissimilar metal of aluminum alloy to copper （I2） and a preliminary analysis of welding parameters influencing on the microstructures and properties of joint was carried out. The results indicated that the thickness of workpiece played an important role in the welding parameters which could succeed in the friction stir welding of dissimilar metal of copper to aluminum alloy, and the parameters were proved to be a narrow choice. The interfacial region between copper and aluminum in the dissimilar joint was not uniformly mixed, constituted with part of incomplete mixing zone, complete mixing zone, dispersion zone and the most region＇ s boundary was obvious. Meantime a kind banded structure with inhomogeneous width was formed. The intermetallic compounds generated during friction stir welding in the interfacial region were mainly CugAl4, Al2Cu etc, and their hardness was higher than oihers.     

10mm厚LF2铝合金搅拌摩擦焊温度分布及组织分析

采用嵌入热电偶测温法得到了10mm厚LF2铝合金搅拌摩擦对焊时不同深度(2、5和8mm)、距离搅拌针不同位置的FSW温度分布;通过对焊缝不同位置的金相观察,分析了温度场对10mmLF2搅拌摩擦焊焊缝金属组织的影响。实验结果表明,返回侧温度略高于前进侧,但最大不超过40℃;焊缝顶部的最高温度出现在与轴肩接触的边缘区域,而焊缝底部的最高温度出现在搅拌针边缘;同时焊缝底部出现的"鼓"形组织表明焊缝不同深度的温度分布不仅与热源产热量有关,还与材料的流动情况有关。     

气液增压装置在闪光对焊机上的应用

针对U型钢专用闪光对焊机的连接工艺要求，设计了专用气液联控的传动机构和增压夹紧机构。介绍了闪光对焊专用夹具的加紧力计算和气液增压原理及其实现，最后介绍了利用气液联合驱动实现动夹具传动机构。