Study on the Behavior of a Surface Oxide Layer during hot Consolidation and Extrusion of Splat-Quenched Aluminum Alloy Tapes.

板淬火铝合金带材热固结和挤压过程中表面氧化层行为的研究。

• 批准号: 60550519
• 负责人: MURAKAMI Yotaro
• 金额: $ 1.22万
• 依托单位: Faculty of Engineering, Kansai University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60550519/
• 关键词: Rapid Solidification; Powder Metullurgy; Al-Li Alloys; Al-Cr-Zr Alloys; 表面酸化皮膜の挙動

In recent years, a powder metallurgy (P/M) method combined with rapid solidification (RS) techniques have attracted considerable attention, because this process could improve elevated temperature mechanical properties and also low density-high modulus. However, aluminum tapes inherently exhibit a surface oxide layer, which affects detrimentally mechanical properties and particularly ductility of P/M products when incompletely broken up or nonuniformly distributed during consolidations and hot working.The object of this study is to clarify the behavior of surface oxide layer during hot consolidation and extrusion of splat-quenched two kinds of alloys, one is Al-Cr-Zr alloys and the other is Al-Li-Zr containing higher concentration of Li than that in an ordinary I/M alloy.In splat-quenching techniques, molten droplets were injected into two kinds of atomospheres, one is experimental laboratory air and the other is dry argon to change the degree of oxidation and hydration.The microstructures of these tapes in the conditions of as-splat as well as heat treated by means of optical, transmission and scanning electron microscopy, selected area electron diffraction and X-ray.The tapes were hot pressed in a vacuum to produce billete, and hot pressed billete were subsequently hot extruded to make wires by extrusion ratio 1 : 20 or 1 : 18.In the hot pressed billets , oxide layers still remains on the prior tape boundary area, and after hot extrusion, the oxide layer were broken up into film fragments.However, the ductility was concluded to be quite different between Al-Cr-Zr and Al-Li-Zr alloys.In the case of Al-Cr-Zr alloys, the ductility was improved by the sufficient hot extrusion, but it was not the case for Al-Li-Zr where it may be necessary to avoid completely a formation of oxide surface layers.

近年来，粉末冶金（P/M）与快速凝固（RS）技术相结合的方法引起了人们的极大关注，因为该方法可以改善高温力学性能，同时还可以改善低密度高模量材料。然而，铝合金带材在凝固和热加工过程中，由于表面氧化层的不完全破碎或不均匀分布，会影响粉末冶金制品的力学性能，特别是塑性。一种是Al-Cr-Zr合金，另一种是比普通I/M合金中Li含量更高的Al-Li-Zr合金。在溅射淬火技术中，将熔融液滴注入到两种气氛中，一种是实验室空气，另一种是干氩气，以改变氧化和水化程度。采用光学显微镜、透射电子显微镜、扫描电子显微镜、选区电子衍射、X射线衍射等手段对带材进行热处理，真空热压成坯料，然后将热压坯料以1：20或1：10的挤压比热挤压成线材。18.在热压坯料中，氧化层仍然保留在先前的带材边界区域上，并且在热挤压之后，氧化层被破碎成膜碎片。然而，结果表明，Al-Cr-Zr合金和Al-Li-Zr合金的塑性有很大的不同，对于Al-Cr-Zr合金，充分的热挤压可以提高其塑性，但对于Al-Li-Zr则不是这种情况，其中可能需要完全避免氧化物表面层的形成。