Failure Analysis of HT200 Wear Brake Drum and Improvement of Its Material

Through macro and micro examination of the damaged wear brake drum of HT200, it was believed that the cause for the failure of wear brake drum was frequent creation of tensile stress and heating in the surface because of strong friction during braking. The mechanism resulting in the failure of wear brake drum was that the cracks in the surface were initiated and extended by tensile stress combined with thermal fatigue, and heavy wear of the working face at elevated temperature resulted from friction. The microstructrue and mechanical properties of wear brake drum were improved by means of microalloying with Cu and Cr to increase its service life.