Thixoforging is a type of semi-solid metal processing at high solid fraction (0.7<φs<1), which involves the processing of alloys in the semi-solid state.Tooling has to be adapted to this particular process to b...Thixoforging is a type of semi-solid metal processing at high solid fraction (0.7<φs<1), which involves the processing of alloys in the semi-solid state.Tooling has to be adapted to this particular process to benefit shear thinning and thixotropic behaviour of such semi-solid material.Tooling parameters, such as the forming speed and tool temperature, have to be accurately controlled because of their influence on thermal exchanges between material flow and tool.These thermal exchanges influence the high-cracking tendency and the rheology of the semi-solid material during forming, which affects parts properties and therefore their quality.Extrusion tests show how thermal exchanges influence quality of thixoforged parts made of 7075 aluminium alloys at high solid fraction by modifying process parameters like forming speed, tool temperature and tool thermal protector.Thus an optimum in terms of thermal exchanges has to be found between surface quality and mechanical properties of the part.A direct application is the evaluation of surface quality of thixoforged thin wall parts made of 7075 aluminium alloy.展开更多
针对核电厂循环水冲洗泵盖板表面结构完整性破坏失效的工程问题,基于冷金属过渡技术(Cold metal transfer,CMT),开展了CuAl9Ni3Fe2铝青铜合金电弧增材修复工艺的研究。通过单层单道成形、单层多道搭接成形以及多层多道试验研究,确定并...针对核电厂循环水冲洗泵盖板表面结构完整性破坏失效的工程问题,基于冷金属过渡技术(Cold metal transfer,CMT),开展了CuAl9Ni3Fe2铝青铜合金电弧增材修复工艺的研究。通过单层单道成形、单层多道搭接成形以及多层多道试验研究,确定并固化了一套CuAl9Ni3Fe2铝青铜合金CMT增材修复工艺的关键参数;并借鉴已有成熟的核电设备制造工程实践,参考RCC-M规范要求,制定了该修复工艺的验证试验要求,明确了试验项目、试验标准及验收指标,并按要求完成试件的制备及试验。结果表明:采用研发的CMT增材修复工艺制备的熔敷金属外观成形优良,内部致密无缺陷且与母材熔合良好,力学性能与母材相当,各项试验结果均满足验收指标。可用于CuAl9Ni3Fe2铝青铜合金的CMT增材制造及修复。展开更多
介绍了铝型材挤压平模CAD系统的总体结构和设计要素.该系统以AUTOCAD12.0为图形支撑环境,VISUAL BASIC4.0 FOR WINDOWS作为开发工具,采用交互式设计,完成了从型材图形输入到模具图纸输出的全过程.利用该系统可以进行挤压平模设计的各项...介绍了铝型材挤压平模CAD系统的总体结构和设计要素.该系统以AUTOCAD12.0为图形支撑环境,VISUAL BASIC4.0 FOR WINDOWS作为开发工具,采用交互式设计,完成了从型材图形输入到模具图纸输出的全过程.利用该系统可以进行挤压平模设计的各项计算,通过优化选择,设计出尺寸精确、结构合理的模具.展开更多
基金University of Liège,Walloon Region (First Europe Program Convention n°"NEP" 415824,THIXALU Project and MAGAL Project) and the COST 541 for their financial support
文摘Thixoforging is a type of semi-solid metal processing at high solid fraction (0.7<φs<1), which involves the processing of alloys in the semi-solid state.Tooling has to be adapted to this particular process to benefit shear thinning and thixotropic behaviour of such semi-solid material.Tooling parameters, such as the forming speed and tool temperature, have to be accurately controlled because of their influence on thermal exchanges between material flow and tool.These thermal exchanges influence the high-cracking tendency and the rheology of the semi-solid material during forming, which affects parts properties and therefore their quality.Extrusion tests show how thermal exchanges influence quality of thixoforged parts made of 7075 aluminium alloys at high solid fraction by modifying process parameters like forming speed, tool temperature and tool thermal protector.Thus an optimum in terms of thermal exchanges has to be found between surface quality and mechanical properties of the part.A direct application is the evaluation of surface quality of thixoforged thin wall parts made of 7075 aluminium alloy.
文摘针对核电厂循环水冲洗泵盖板表面结构完整性破坏失效的工程问题,基于冷金属过渡技术(Cold metal transfer,CMT),开展了CuAl9Ni3Fe2铝青铜合金电弧增材修复工艺的研究。通过单层单道成形、单层多道搭接成形以及多层多道试验研究,确定并固化了一套CuAl9Ni3Fe2铝青铜合金CMT增材修复工艺的关键参数;并借鉴已有成熟的核电设备制造工程实践,参考RCC-M规范要求,制定了该修复工艺的验证试验要求,明确了试验项目、试验标准及验收指标,并按要求完成试件的制备及试验。结果表明:采用研发的CMT增材修复工艺制备的熔敷金属外观成形优良,内部致密无缺陷且与母材熔合良好,力学性能与母材相当,各项试验结果均满足验收指标。可用于CuAl9Ni3Fe2铝青铜合金的CMT增材制造及修复。
基金Projects(51104043,51374067)supported by the National Natural Science Foundation of ChinaProject(2012CB619506)supported by the National Basic Research Program of ChinaProject(N120409002)supported by the Fundamental Research Funds for the Central Universities,China
文摘介绍了铝型材挤压平模CAD系统的总体结构和设计要素.该系统以AUTOCAD12.0为图形支撑环境,VISUAL BASIC4.0 FOR WINDOWS作为开发工具,采用交互式设计,完成了从型材图形输入到模具图纸输出的全过程.利用该系统可以进行挤压平模设计的各项计算,通过优化选择,设计出尺寸精确、结构合理的模具.
