Microstructure and mechanical properties in heat-affected zone of large-thickness steel ingot cut with oxygen-propane flame

The machining allowance of precision metal cutting machine tools depends on the microstructure evolution in heat-affected zone during flame cutting. In this paper,900 mm thick 34CrNiMo6 steel and 450 mm thick 45 carbon steel ingots were cut using an oxygen-propane flame. Then,the macroscopic morphology and microstructure in the heat-affected zone were examined to analyze the influence of microstructure evolution on the performance of workpieces. The range of heat-affected zone and machining allowance were determined to optimize the parameters during cutting and after cutting process.