Research On Low-Temperature Thermal Deformation Behavior Of HG785D Steel And Finite Element Analysis Of Hot Straightening Process

With the increasing development of the plate controlled rolling and controlledcooling technology (TMCP), a hot rolling plate plant according to market demand todevelop the hg785d high strength low alloy steel, the steel has good low temperatureimpact toughness, low thermal expansion coefficient and stability of elastic modulus,manufacturing, mining machinery, heavy machinery, ships, super steel shell, pressurevessel and so on high strength products the ideal material. Straightening is an essentialstep in the production of medium plate, and the accuracy of straightening model willdirectly affect the product performance and production cost.. Due to the lack of lowtemperature deformation flow stress data, it is difficult to optimize the straighteningprocess and the accurate calculation of the force and energy parameters..Therefore, itis of great significance for the research on the behavior of the low alloy high strengthsteel HG785D in the low temperature zone. The main research contents of this articleare as follows:(1)By using Gleeble-1500thermal simulation testing machine of steel specimensfor single pass compression test and analysis of different process parameters onhg785d steel low alloy high strength steel low temperature hot deformation flowstress;(2)The mathematical model of the initial stress, peak stress, peak strain and Zparameter was established by using thermal simulation experiment data, and theactivation energy of the low temperature deformation of the test steel was calculated;(3)According to the flow stress-strain curves of the experimental steel, the stressmodel of the process hardening dynamic recovery and the dynamic recrystallizationflow in the low temperature zone was established;(4)The straightening force calculation model of the plate heat straighteningprocess is established according to the elastic-plastic bending theory;(5)The finite element simulation analysis of the thermal straightening process iscarried out by using the finite element simulation software of theANSYS/LS-DYNA.The simulated value of the straightening force is in good agreement with the measured values.Research results can be used for prediction of plate straightening machinestraightening process of straightening force, for plate heat straightening straighteningtechnology parameter setting and straightening process optimization has practicalsignificance and higher theoretical value.