%0 Journal Article %T Cause Analysis of Crack Formation in HRB400 Screw-Thread Steel %A Pengbiao Wang %A Qichun Peng %A Sanxiang Lei %A Youhua Wang %J International Journal of Nonferrous Metallurgy %P 16-21 %@ 2168-2062 %D 2016 %I Scientific Research Publishing %R 10.4236/ijnm.2016.52003 %X The analysis of the crack on the HRB400 screw-thread steel surface has been carried out by means of metallographic microscope, scanning electron microscope and EDAX. It is shown that the type of inclusions in the crack steel samples is mainly class B oxide, C silicate, and the inclusion size of the majority below 10 ¦Ìm, and a small number of large inclusions are observed. The content of oxygen in the steel is high, and the carbon segregation is the main reason of the crack formation of HRB400 screw-thread steel. The measures to improve the crack formation of HRB400 screw-thread steel are put forward, which provides a powerful basis for the practical production. %K HRB400 Screw-Thread Steel %K Crack %K Inclusion %K Cause Analysis %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=65625