Healing of Double-Oxide Film Defects in Commercial Purity Aluminum Melt

被引：30

作者：

Bakhtiarani, Fatemeh Najafzadeh ^{[1
,2
]}

Raiszadeh, Ramin ^{[1
,2
]}

机构：

[1] Shahid Bahonar Univ Kerman, Dept Met & Mat Sci, Kerman 76169, Iran

[2] Shahid Bahonar Univ Kerman, Mineral Ind Res Ctr, Kerman 76169, Iran

来源：

METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE | 2011年 / 42卷 / 02期

关键词：

REDUCED PRESSURE TEST; POROSITY;

D O I：

10.1007/s11663-011-9480-y

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The possibility of the formation of bonding between the two layers of a double-oxide film defect when held in a commercial purity liquid Al alloy was investigated. The defect was modeled experimentally by maintaining two aluminum oxide layers in contact with one another in a commercial purity Al melt at 1023 K (750 degrees C) for times ranging from 7 minutes to 48 hours. Any changes in the composition and morphology of these layers were studied by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The results showed that the oxide layers started to bond to one another after approximately 5 hours, and the extent of the bonding increased gradually by the holding time. The bonding is suggested to form because of the transformation of gamma- to alpha-Al2O3. A complete bonding formed between the layers only when the oxygen and nitrogen trapped between the two layers were consumed, after approximately 13 hours. The results also confirmed that the nitrogen within the atmosphere of an oxide film defect reacts with the surrounding Al melt to form AlN at the interface of the defect and the melt. DOI: 10.1007/s11663-011-9480-y (C) The Minerals, Metals & Materials Society and ASM International 2011

引用

页码：331 / 340

页数：10

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