半固态金属成形技术的研究现状及应用展望

介绍了半固态金属的形成机理、制备方法和近几年来该加工技术的发展现状,综述了国内外半固态金属成形技术的应用情况,并对我国半固态金属成形技术的发展动向进行了讨论.     

金属材料半固态凝固及成形技术进展

简要介绍了金属材料半固态凝固及成形技术发展的历史和现状,重点介绍了近年开发的几种金属材料半固态凝固制备技术的代表性方法与特点、铝合金和镁合金等轻金属材料半固态凝固及流变成形的组织与性能、高熔点合金材料半固态凝固制备及成形技术的进展以及半固态凝固成形技术的应用现状,最后对金属材料半固态凝固及成形技术的进展状况及发展前景作了简单的总结和展望。     

镁合金半固态注射成型在笔记本电脑上应用

镁合金半固态注射成型技术是一项新型加工技术,已经广泛应用于汽车、5G、3C和军工等行业,有着较好地应用前景。以重庆笔电产业为背景,就镁合金半固态注射成型技术在笔电上应用,介绍了镁合金半固态注射成型基本概况,描述了镁合金半固态注射加工原理,材料,模具、设备和成型后的后续加工情况,分享了笔电上产品应用案例,并对重庆笔电产业发展镁合金半固态注射成型技术寄予期待。     

Mushy/Semi-Solid Metal Forming Technology - Present and Future

Mushy, semi-solid and/or thixo processing of metals (alloys) is becoming popular as a new potential manufacturing technology for parts and components in automobile, electronic and machine industries. Internal structures and mechanical properties of those metals that include solid and liquid fractions are quite different from those of hot or molten metals. Diversified possibilities are known today to process those metals based on die casting, hot metal forming or polymer injection technologies, each of which has its own specific advantages and disadvantages. Up to now thixocasting and thixomolding have been used in industrial applications for light metal alloys. The potentials of those processes are wider by far however. They include the processing of specially designed alloys and composites, the combination of forming and joining processes as well as reduction of production costs and energy consumption.     

半固态成形轻合金的发展状况

半固态成形技术以其高效、节能、近净形生产以及成形件性能高等诸多优点，已成为21世纪最具发展前景的金属成形工艺之一，但是半固态成形轻合金应用品种的局限性，制约了半固态成形技术的发展。文中介绍了国内外半固态成形轻合金的研究、应用状况以及新型半固态轻合金的设计开发，并分析了半固态成形轻合金的发展前景。     

半固态坯料制备工艺的研究进展

半固态坯料制备是半固态成形技术的关键,其工艺方法多种多样,而又各有优缺点,工艺参数的优化和新工艺的开发是国内外研究的热点之一;总结了近年来半固态坯料制备在国内外的最新进展,从半固态坯料制备工艺的发展历程角度详细分析了各种工艺方法的原理、工艺参数、优缺点和发展前景。     

Shear band formation in shaped rheocast aluminium component at various plunger velocities

Significant progress has been made in recent years in understanding and modelling the rheology of semi-solid metals. These models show the effects of the microstructure in terms of size and morphology of globules on the material response. More recently it has been shown that semi-solid metals can behave as compacted granular materials such as sand. A particular signature of such deformation is that the deformation becomes concentrated into shear bands which are 10-20 grains wide. Such bands have also been observed in a range of cast products. Recently, it has been clearly shown that shear bands in high pressure die cast (HPDC) products are also the results of Reynolds dilatancy. Shear bands are also known to be a common feature in semi-solid metal products. The segregation banding in semi-solid metal (SSM) material and its dependence of plunger velocity were investigated. Shaped castings were made with the RHEOMETAL? process with a range of different plunger velocities. The microstructural characteristics were investigated, with a particular emphasis on shear bands. It is shown that ingate velocities influence the location and characteristics of the shear bands.     

ZA27合金半固态模锻成形性能的研究

采用模具对ZA27合金进行半固态模锻成形,对比分析了成形工艺参数对成形零件表面质量以及内部组织的影响,探讨了半固态金属的变形机理。结果表明,成形温度在475℃左右时的制件表面平整光滑,内部组织较致密;高的变形速率更有利于组织均化;随变形温度的不同,半固态ZA27合金呈现不同的变形机理。     

挤压铸造高品质大型结构件

大型结构件的高品质整体成形是零件制造领域的难题。挤压铸造以整体流变补缩解决了重力铸造补缩效率低和收缩缺陷的问题,又以良好的流变充型能力突破了固态锻造技术设备能力的限制,成为大型结构件高品质整体成形制造的新选择。实践证明,使用专用涂料、铸造模具代替锻造模块并对模具温度进行有效调控是降低模具成本占比的有效途径。局部多点加压、复合挤压以及随流半固态挤压铸造都是显著降低设备投资、确保高品质成形的有效措施。     

Microstructural evolution during RAP process and deformation behavior of semi-solid SKD61 tool steel

Semi-solid forming technology has several advantages over the conventional metal forming process owing to the unique behavior and characteristic microstructure of metals in the semi-solid state. With the aim of establishing a shorter process chain for manufacturing the high-quality tools required for forming, the microstructural evolution and basic deformation mechanism of the hot-working tool steel SKD61 in the semi-solid-state were studied experimentally. The feasibility of the recrystallization and partial melting (RAP) process for the fabrication of SKD61 stock with a uniform spherical microstructure was validated. The effects of parameters in RAP processing, such as the predeformation temperature and predeformation ratio, on grain refinement were systematically clarified. Finally, the effects of semi-solid forming parameters, such as the forming temperature, forming ratio and strain rate, on the morphology of the microstructure and the flow stress were also investigated.     

近液相线铸造法半固态成形工艺的现状及发展前景

阐述近液相线铸造法的制浆和组织演变机理,并与其他半固态成形方法进行了比较,综合评述了各种参数对近液相线工艺的影响。从有色金属、高熔点合金钢方面介绍近液相线法的研究现状、最新研究成果及其存在的问题。展望近液相线法成形工艺的发展前景。     

半固态金属浆料制备新技术

半固态加工技术具有许多优良的特点，近年来得到迅速发展。广泛用于生产半固态金属的方法为触变成形，而流变成形与触变成形相比，前者更节约能源、流程更短、设备更简单，因此流变成形技术将是金属半固态加工技术的发展方向。半固态加工技术的发展趋势是，进一步简化加工工艺流程，进一步降低加工成本，扩宽半固态加工技术的应用范围。本文主要介绍最近几年在半固态浆料制备和加工中的几种新工艺和新技术的原理、特点及其应用，其中有新MIT工艺、冷却斜槽法、双螺旋流变注射成形法、剪切一冷却一轧制法、NRC工艺、不同液体混合法、近液相线铸造法等方法。     

半固态铸造技术研究现状与展望

半固态铸造是一种新的材料成形技术，综述了半固态铸造合金的组织变化、坯料制备、充型过程数值模拟和应用等方面的研究成果，同时对我国发展半固态铸造技术提出了若干值得重视的问题。     

Research and Applications of Semi-solid Processing

Since it was pioneered by Flemings and otherresearchers [11, the semi-solid metal processingtechnique has been widely stUdied in the world.Especially in the past decade, SSM as a newproduct forming technique has been rapidly developed and put into commercial applications[2, 31. In recent years, with the development ofthe ado-industry of China, a lot of researchwork on SSM has been done, including the preparation of slumes, reheating and thixoforming[Al6]; moreover, great achievements have …     

微成形热挤压试验及模具设计

介绍了采用半固态ZL101铝合金进行挤压成形微型齿轮的试验研究,设计了挤压模具和加热及温控系统.试验结果表明,挤压过程中的坯料温度对零件质量产生重要影响,它决定了半固态合金的触变特性,合适的半固态加工技术可以成形微型零件.     

半固态金属加工技术的数值模拟研究新进展

对近期国内外半固态金属加工技术的数值模拟进行了系统论述，介绍了流变学行为、二次加热和触变成形的模拟进展及应用现状，并对半固态金属加工过程模拟的发展进行了评价。     

半固态材料成形应用

半固态加工是金属材料热加工的新兴技术，它与固态加工、液态加工同属金属加工领域：主要介绍了半固态金属浆料的制备、半固态加工的工艺方法、半固态加工的应用及未来发展趋势，以期推动其理论研究和工业发展。     

稳步发展的压铸技术——第五届中国国际压铸会议论文综述

介绍了“第五届中国国际压铸会议”关于压铸学术交流概况,对压铸生产的发展状况,铝合金压铸、半固态技术的发展,镁合金压铸、半固态技术的发展,计算机模拟技术在压铸中的应用、挤压技术的研究发展和其它方面等6个部分的会议论文进行了评述,并提出了未来压铸行业的工作重点。     

半固态材料成形评述

半固态加工与固态加工、液态加工同属金属加工领域,是金属材料热加工的新兴技术。主要介绍了半固态加工 的应用及未来发展趋势,以期推动其理论研究和工业发展。     

镁合金半固态研究进展

本文首先介绍了镁合金半固态研究背景,进而从镁合金半固态成形合金设计、镁合金半固态成形工艺研究、镁合金外场处理下半固态成形,以及镁合金半固态成形过程模拟四个主要方面介绍了镁合金半固态成形技术的现状。从近十年的研究结果得出：镁合金耐腐蚀性增加、晶粒明显细化、尺寸更加均匀、制备了细小的等轴的再结晶组织半固态浆料、获得力学性能更佳、对产品缺陷进行预测、实现了工艺优化。进一步完善和创新了镁合金半固态工艺,对推动镁合金发展具有重大的意义,并对镁合金半固态成形未来的发展方向进行了展望。