Test material and heat treatment process The ingot containing 0.117% Nb (mass fraction) was melted in 15 kg medium frequency induction furnace. The chemical composition of the steel was determined by pmi-masterpro mobile direct reading spectrometer. The ingot was homogenized annealed at 1100 ℃ for 2 h, then quenched...
30cr13 martensitic stainless steel has good mechanical properties, hardenability and corrosion resistance, which is widely used in medical devices, measuring instruments and molds. The low temperature toughness and strength of 30cr13 steel can be significantly improved by the dispersion precipitation of carbon and nitride (size less than 5 nm)...
1.Characteristics of wear resistant steel ball The composite wear-resistant casting steel ball has excellent comprehensive properties such as high strength, strong toughness and fatigue resistance. The steel ball is made of manganese, silicon and nickel as phase change elements. After compound inoculation and special heat treatment process, the high...
The steel ball used in ball mill can be divided into casting ball and forging ball. Generally, the diameter of casting ball is less than 120mm, which is used in ball mill; large diameter mill or semi autogenous mill requires larger diameter of steel ball, which is basically forged...
The properties of tensile samples were tested by a universal testing machine controlled by microcomputer, and the tensile strength and lower yield strength of each sampling part were tested. With the different sampling locations, the tensile strength and yield strength of cast steel castings produced by the same foamed...
Six groups of samples were taken when analyzing surface carburization, and the location of the test point was changed to the center of the sample section, so as to analyze the volume carburization and carbon content test results inside the casting. It can be seen that the influence degree...
In this test, 6 test pieces were poured in the same ladle of molten steel. The chemical composition of molten steel was detected before pouring, and the initial carbon content was 0.09%. After casting is completed and the casting is cooled down, the box is opened for sand dropping,...
In order to study the carburization defects of steel casting for bridge support, four sampling locations are selected, namely, near the inner gate, the center of the casting, the rib plate part and the top of the casting (the part connected with the riser), which are numbered as a,...
Firstly, the mechanism and manifestation of carburization defects in steel castings are described, and then the experimental methods and main masters of the research on Carburization defects of steel castings for bridge bearings are planned, and the detection and verification are carried out through the tests, and the following...
The filling process of lost foam casting is the replacement process of metal liquid and foam pattern. Because the pouring temperature of molten steel is high (above 1550 C), the gasification and cracking of foam pattern are relatively sufficient, resulting in a large amount of elemental carbon. Carbon diffuses...