Requirements of High Temperature Materials

Abstract

Selection of a material for reliable economic performance in a particular application must take account of many factors. Chemical resistance to the environment involved, mechanical behaviour and physical properties are of prime importance. In many applications involving high temperature, economic performance requires long life, up to several years in many industrial situations. During this time, the operation may involve many plant start-ups and shutdowns and not all of the operations involve the highest process temperatures. In some applications it is found that the low temperature stages of the operation may be the most damaging in corrosion terms. Thus, more than any other area where materials are used, high temperature applications may demand multi-material components if the design requirement is to be achieved. The material from which the component is made essentially meets the mechanical requirements of the operation and provides a modicum of environmental resistance, while a coating which is chemically and physically compatible with the base material may be necessary to provide the overall environmental resistance.