Spray Etching Rate Development of Stainless Steel in the Etchant for Printed Circuit Heat Exchanger Channels

Abstract

As a new type of heat exchanger, printed circuit heat exchanger (PCHE) has high compactness and can work under high-temperature, high-pressure and other extreme conditions. Therefore, it is proposed to be used as the intermediate heat exchanger under very high temperature gas cooled reactor and other special operating environment, especially nuclear reactor system. The chemical etching technology is one of major processes for PCHE manufacturing. In order to predict the etching rate under different etching conditions and realize the heat transfer units controllable production, this paper studied the influence of channels initial width, etching time, spray pressure and etchant temperature on the etching rate by experiment and mathematical analysis. A relative correlation for the spray pressure and etching temperature, etc. on the etching rate in the specific etchant of 300 g·L-1 FeCl3 60mL/L HCl 1M H3PO4 was established, which lessens experiment times and enhances the understanding of every factor on spray etching rate to realize the low-cost, high-efficiency production of PCHE heat exchanger units.