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）方法与快速凝固（RS）技术相结合引起了人们的广泛关注，因为该工艺可以提高高温力学性能以及低密度高模量。然而，铝带固有地表现出表面氧化层，当在固结和热加工过程中不完全破碎或分布不均匀时，该氧化层会不利地影响粉末冶金产品的机械性能，特别是延展性。本研究的目的是阐明表面氧化层的行为两种合金在溅射淬火过程中的热固结和挤压过程中形成的层，一种是Al-Cr-Zr合金，另一种是Li浓度高于普通I/M的Al-Li-Zr合金在溅射淬火技术中，将熔融液滴注入两种气氛中，一种是实验实验室空气，另一种是干燥氩气，以改变氧化和水合程度。这些带材在溅射条件下的微观结构以及通过光学、透射和扫描电子显微镜、选区电子衍射和X射线等手段进行热处理。带材在真空中热压以生产方坯，热压方坯随后被热挤压按1：20或1：18的挤压比制成线材。热压坯料中，原带边界区域仍残留有氧化层，热挤压后，氧化层破碎成薄膜碎片。但延展性下降结论是 Al-Cr-Zr 合金和 Al-Li-Zr 合金之间有很大不同。对于 Al-Cr-Zr 合金来说，充分的热挤压可以提高延展性，但对于 Al-Cr-Zr 合金来说，延展性却有所提高，但对于Al-Li-Zr，其中可能需要完全避免氧化物表面层的形成。