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一、前言英国通用规范BS1400AB2中所包括的镍铝青铜(NAB)铸造合金在海军中有广泛的用途。在这一通用规范中,目前在澳大利亚皇家海军中用作阀门、部件的镍铝青铜铸造合金有两种不同的DGS规范。原来的铸件按联合王国规范DGS8520制造,而近年来的铸件按取代它的DGS348规范制造亡。这两个规范除成分上有微小差异外,它们的一个主要差别在于第二个规范要求的热处理温度低得多。已在以下两方面予以关注[3];首先,新规范可能导致耐蚀性降低;其次,难于在拉力试验中获得规定的伸长率值。因此,本文将评述合金成分的变化、金相组织特征和热处理温度对上述规范中的NAB的机械性能和耐蚀性的影响。
I. Preface The nickel-aluminum bronze (NAB) cast alloy included in the British Common Specification BS1400AB2 has a wide range of uses in the Navy. In this general specification, there are two different DGS specifications for nickel-aluminum-bronze cast alloys currently used as valves and components in the Royal Australian Navy. The original castings were made according to the United Kingdom Code DGS8520, whereas castings in recent years were manufactured to replace its DGS348 specifications. One of the major differences between the two specifications, except for minor differences in composition, is the much lower heat treatment temperature required by the second specification. Attention has been paid to both the following two aspects; first, the new specification may lead to a decrease in corrosion resistance; secondly, it is difficult to obtain a prescribed elongation value in a tensile test. Therefore, this article reviews the changes in alloy composition, microstructure and heat treatment temperature on the NAB in the above specifications of the mechanical properties and corrosion resistance.