Diffusion-hardening effect on the technological properties of high-temperature steel

Abstract

The possibility of long-term operation of DIN: 1.7715 (12Cr1MoV) ferritic-pearlitic steel with high surface layer chromium content on the heating surfaces of high-power boilers has been studied. Diffusion hardening of pipes is proved to be an effective method for increasing the durability and reliability of power equipment. The use of diffusion chroming of heatresistant ferrite-pearlite steels has made it possible to increase their oxidation resistance at operating temperature. By means of optical microscopy and mechanical tests the possibility of increasing the operational duration of heat-resistant ferritic-pearlitic steels, without reducing the of technological properties indicators has been demonstrated. The aspects of temperature, corrosion resistance and mechanical strength are presented. The experience of industrial operation of diffusion chromized and heat-hardened pipes of DIN: 1.7715 as boilers heating surfaces is generalized. The possibility and effectiveness of this method on the example of capacities of Trypil'skaTPP are shown.