Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《材料研究学报》
Abstract: Polyurethane coatings with two kinds of sillitin, i.e. M type and Z type sillitin respectively as filler were prepared and sprayed on hot dip galvanized steel sheets. The coatings exhibited better mechanical properties than the simple polyurethane coating, i.e. the wear resistance and the hardness of the polyurethane coating may be enhanced by 57.1% and 14.5%, as well as 85.7% and 41.8% for the addition of M type and Z type sillitin respectively. The coatings with the two types of sillitin exhibited also better corrosion resistance. The reason is that two types of sillitin are of a special structure composed of micro- sized granular silica and nano- flake kaolin clay, and the sillitin possesses high amount of nanoflake, which may be beneficial to the enhancement of the permeation resistance and mechanical properties of the coatings.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《材料研究学报》
Abstract: Oxidation behavior of two ferrite/martensite(F/M) steels, namely a novel 9%-12% Cr modified F/M steel (SIMP steel) and a commercial T91 steel were comparatively studied in air at 800oC. The oxide scales formed on the two steels were characterized by XRD, SEM and EPMA. The results show that the oxide scale formed on SIMP steel is single-layer composed of Cr2O3 and Mn1.5Cr1.5O4 spinel particles, and Si was enriched at the interface between the chromia scale and matrix; while the oxide scale formed on T91 steel has a double layered structure with an outer hematite Fe2O3 layer and an inner Fe-Cr spinel layer. The SIMP steel has better high temperature oxidation resistance than T91 steel, which may be due to the higher content of Cr and Si beneficial to the formation of the compact oxide scale on the SIMP steel.