非晶合金零件成形技术研究进展

The Forming of Amorphous Alloy Parts: a Technological Review

非晶合金作为一种结构不同于传统晶体金属、性能优异的新型材料一直是凝聚态物理学家和材料学家关注的热门领域。近几十年来,非晶合金的基础理论研究和制备工艺都取得了巨大进步,非晶合金作为一种极具应用前景的结构材料和功能材料,正在逐渐由实验室走向商业应用,推动科技发展。一种新材料想要最终走向商业应用,必须要有与之相适应的高生产率、低成本的零件成形技术。但是非晶合金的制备需要较快的冷却速率、高真空、高纯原料等苛刻条件,成本相对较高。同时非晶合金在室温下强度高、脆性大的特性使其难以机加工,热塑性成形时又极易发生晶化,难以成形大尺寸、复杂形状的零件,这严重限制了它的广泛应用。针对非晶合金的特点开发相应的零件成形技术成为学者们研究的重要课题。随着非晶成形能力较强的合金体系的出现,相应的非晶零件成形技术也得到了极大的发展。目前非晶合金的零件成形技术主要包括铸造成形、热塑性成形、焊接、粉末烧结、增材制造技术等,成形零件的尺寸极限跨及纳米至厘米尺度,复杂程度、制备和成形效率都得到大幅提升。但是每种成形技术都在成形效率、尺寸、性能、成本等方面有些许局限性,难以完全实现非晶合金零件的工业化生产和应用。本文简要综述了目前非晶合金铸造成形、热塑性成形、焊接、粉末烧结、增材制造技术的最新研究进展,分析了现有成形技术的优缺点及非晶合金成形的难点,最后指出外加能场复合、多种工艺复合的复合制造方式将是非晶合金零件成形技术未来发展的重要方向。

As a new class of materials with excellent properties and different structure compared to traditional crystal metals,amorphous alloys havebeen attracting great interest from condensed matter physicists and materials scientists. In recent decades,the basic theoretical research and preparation technology of amorphous alloys have made great progress. Amorphous alloys,which posses wide application prospects as structural materials and functional materials,are gradually moving from laboratory to commercial applications and promoting the development of science and technology.To realize the commercial application of a new material,it is necessary to have high productivity and low-cost manufacturing technology of parts. However,as the preparation of amorphous alloys requires rapid cooling rate,high vacuum,high purity raw materials,the cost is relatively high. Moreover,the high strength and high brittleness at room temperature make the amorphous alloys difficult to be machined,while crystallization is easy to occur during the thermoplastic forming process. In brief,it is still difficult to fabricate amorphous alloy parts with large size and complex shape,which seriously restricts the wide application of amorphous alloys. Thus,it has become an important subject for scholars to develop the novel part forming technologies according to the characteristics of amorphous alloy.With the appearance of alloy system with strong amorphous forming ability,the forming technology of amorphous alloy parts has also been greatly developed. At present,the forming technology of amorphous alloys mainly includes casting forming,thermoplastic forming,welding,powder sintering,additive manufacturing technology,etc. The size limit of the formed part spans from nanometer to centimeter,and the complexity,preparation and forming efficiency are also greatly improved. However,each forming technology has some limitations in forming efficiency,size,performance and cost,which makes it difficult to fully realize the industrial production and application of amorphous alloy parts.This paper reviews the latest research progress in the forming technologies of amorphous alloys,including casting,thermoplastic forming,welding,powder sintering and additive manufacturing. The advantages and disadvantages of existing forming technologies and the difficulties in amorphous alloys forming are also analyzed. Finally,it is pointed out that combining of different processing methods and introducing external energy fields may be important development directions for the fabrication of amorphous alloy parts in the future.