喷射沉积多孔材料楔形压制工艺的研究现状与发展趋势

Status and Development Trend of Wedge Pressing Technology for Spray-Deposited Porous Materials

楔形压制技术是一种基于多道次局部小变形累积致整体成形实现大尺寸喷射沉积多孔材料的致密化的先进工艺。本文综述了喷射沉积多孔材料的致密方法,对比了楔形压制与其他传统致密方法,说明了采用楔形压制工艺的优势和必要性;分别介绍了喷射沉积方形件、环形件与管形件楔形压制的原理、技术特点及研究应用;分析了楔形压制工艺存在的一些局限性;展望了楔形压制技术的发展趋势,认为梯温楔形压制的温度梯度控制精度有待提高;环形件楔形压制的致密均匀性和压制工艺有待进一步深入研究;管形件楔形压制则在压制效率和压制后管坯的尺寸精度有待提高;楔形压制工艺应拓展到其他形状坯料的致密或预成形,也不应局限于坯料的致密,可发展为成形工艺,拓展楔形压制的应用范围。

Wedge pressing is an advanced densification technology for compressing spray-deposited porous preforms of large scale by accumulating deformation as to integral forming. Densification method of spray deposited porous materials is introduced. Wedge pressing is compared with traditional compressing methods to reflect superiority and necessity of wedge pressing adopting. Principle, technical characteristics and research utilizes of wedge pressing are introduced separately, and limitations and development trends of this technology are analyzed. It is considered that control accuracy of temperature gradient of temperature gradient wedge pressing should be improved;compact homogeneity and compact process of ring billet should be investigated further;and compact efficiency and dimensional accuracy of tubular billet as pressed should be improved. Wedge pressing will be applied to compaction or preforming of billet of other shapes except bulk, ring and tube. Furthermore, wedge pressing should not be restricted to densification;it can be developed into a forming technology to expand its application range.