Numerical Simulation Study On The Influence Of Geometric Factors On Forging Internal Defects Of Forged Ingot

The quality of large—scale forging connects with the quality of ingot closely.It is necessary to control the solidification process to obtain the high quality ingot.In this paper,a general purpose commercial finite element method software Anycasting is used for simulation of the three dimension temperature and thermal stress field of ingot mould and steel ingot in solidification process.The mathematical models of transient state temperature field and elastic-plasfic stress field are established using suitable simulation hypotheses and considering the changing material property with temperature.By changing the ingot different geometric factors, mainly including, the change of the ingot taper, cap volume ratio, high aspect ratio, the ingot mould wall thickness of 24 tons of forging ingot temperature distribution in the solidification process change has carried on the numerical calculation and analysis;Calculation results show that in the design of other parameters constant, the change of the single ingot of factors will affect the quality of solidification, internal loose more than height to diameter can make ingot shrinkage cavity defects throughout the scope is big, but can reduce the center defects, increase the taper of the ingot can facilitate liquid steel order flow down, reducing the shrinkage cavity defects; Single increasing vertical height of the riser, fever may make ingot bottom distance place far away, on the longitudinal vertical increase the height of the riser of steel ingot has not got very good effect; Increase the cooling and solidification of ingot mold wall thickness can improve the speed; When the wall thickness increased to a certain degree, the impact on the solidification speed is gradually weakened, the mold wall thermal stress increases with increasing wall thickness.In addition, this article also to various factors on the solidification of liquid steel in the primary and secondary order orthogonal scheme is analyzed. In different location of the ingot, the different factors on the internal effect of shrinkage cavity defects is not the same, is at the bottom of the ingot, the primary and secondary order of loose defect of lower influence ingot R high taper diameter than the wall thickness Slenderness ratio> wall thickness > taper > cap capacity ratio; In the center of the ingot ingot taper effect of shrinkage cavity in order to taper > wall thickness > cap capacity ratio> Slenderness ratio; In the first half of the steel ingot affect ingot taper internal loose order of shrinkage cavity for taper>cap capacity ratio >Slenderness ratio>wall thickness to diameter ratio.The numerical simulation of solidification process is studying emphasis and inevitable trend in the lab of solidification field.This method is applied to analyzing the change of temperature.