Research on the Microstructure and Mechanical Properties of Prefabricated Building Steel Structures
XU Jing
LU Xiangyou
Abstract：To improve the tensile properties,hardness,and low-temperature impact toughness of prefabricated building steel structures,the effects of austenitizing temperature and quenching cooling medium on the microstructure,hardness,tensile properties,and low-temperature impact properties of prefabricated building steel were investigated.The results show that at different quenching temperatures,the metallographic structure of the test steel consists of martensite and residual austenite;increasing the quenching temperature increases the austenite grain size and lath martensite width of the test steel.As the austenitizing temperature rises from 850～940℃,the strength and microhardness of the test steel increase,while its toughness and plasticity(elongation after fracture,reduction of area,and-20℃impact energy)gradually decrease.When the austenitizing temperature is 910℃,the test steel exhibits high strength and plasticity as well as high-20℃impact energy,making it the optimal austenitizing temperature.Under the three cooling rates,the metallographic structure of the test steel is lath martensite and residual austenite;the faster the cooling rate,the finer the grains and lath martensite structure of the test steel,and the higher its strength and hardness.When the cooling medium is 8 wt.%NaCl solution,the grain size and lath martensite bundle size of the test steel are the finest.
Keywords：prefabricated buildingsteel structurequenching and temperingmicrostructuremechanical properties
Publication Date：2026-03-20
Online Publishing Date：2026-03-31(First online date of this platform, not the publication date of the document)
Pages：5( 102-106 )