1997 Volume 83 Issue 4 Pages 263-268
The microstructure of heat resisting steels and alloys for high-temperature plants changes depending on operating conditions and time. The microstructural changes affect the mechanical properties of the materials at high temperatures. Microstructural examination of the materials is generally carried out using etching techniques by chemical method. For chemical etching, however, high skill is required to produce clear microstructure.
In this research, penning discharge micro-sputtering techniques were applied for etching a variety of heat resisting steels and a super alloy. The etching of 1Cr-1Mo-0.25V ferritic and 316H austenitic steels and Ni-base Inconel 713C superalloy was carried out in the vacuum chamber of a micro-sputtering apparatus..All of the materials exhibited clear microstructure using micro-sputtering, irrespective of different chemical compositions and different history of the materials. The grain boundaries, creep voids and precipitates such as carbides and σ phase were characterized. It was concluded that the present method required lesss skill and the resultant microstructure was insensitive to sputtering conditions.