Papers by Keyword: Thermal Shock Property

Abstract: The thermal shock and hydration resistance property of the light heat-insulation refractory materials is studied, which were prepared using high calcium magnesia slag as main raw materials. The phases and microscopy were characterized by means of X-Ray diffraction (XRD), field emission scanning electron microscope (FE-SEM). The results show that the main crystalline phase is CAS₂, and it is with low volume density, excellent thermal shock and hydration resistance property.

Abstract: Three kinds of coating materials, namely Cr2O3 ceramic, Al2O3-TiO2 ceramic and WC-Co cermet, were screened and sprayed on the surface of valve ball by plasma spraying technology, and two kinds of brush plating materials, namely high speed nickel and nickel tungsten, were also screened and brush plated on the surface of valve seat by electrical brush technology. The microstructure and morphology of the plasma sprayed coatings were analyzed by means of scanning electron microscopy. The tribological properties of the plasma sprayed coatings sliding against the high speed nickel and nickel tungsten layers were investigated on a pin-on-disc friction and wear tester. The microhardness, thermal shock property and bonding strength of the coatings were also tested. The results indicate that the sealing pair composed of the valve ball with the plasma sprayed coating of Al2O3-TiO2 and the valve seat with the brush plating layer of nickel tungsten has the best combination property.