Study On Casting Service Performance Prediction Method Based On The Defect Information

The quality of Casting is closely related to the casting process, productionenvironment, and alloy materials with complex solidification behavior andorganizational structure form, thus easy to lead to a variety of casting defects, such asshrinkage cavity, shrinkage porosity, slag inclusion and cracking, etc.). Sometimescasting defects are unavoidable, it usually takes a lot of time and funds to eliminatedefects, but the defects is very hard to to eliminate and it also increases the cost.However, casting defects, especially the hole defects in casting are difficult toeliminate, it often used for detecting methods such as ultrasonic flaw detection, itscost further improved, which makes the casting in the engineering application is oftenby increasing the size of its key parts to increase its safety coefficient, but when itincrease in size only to improve the bearing capacity of the parts, and due to the holedefects easy cause stress concentration, and the stress concentration point oftenbecome casting the origin of the fatigue crack initiation site, so you can’t effectivelyimprove the fatigue life, sometimes even lower, at the same time can also cause thewaste materials.The characterization of defects is very complex, which leads to can’t toconstructi mechanical model containing defects at present. So most of the researcherson the casting structure analysis does not take into account the casting defects on itsstructure analysis, which makes the simulation analysis results and the actualsituation much difference.This paper on the basis of the use of3d reconstruction method to obtain thethree-dimensional model containing hole defect feature and adopts the method ofserial section of casting slice, and extractis defect information and maps it to the finiteelement unit grid model, which is obtained with the hole defect of heterogeneousfinite element unit grid model, eventually to contain the hole type of defectinformation heterogeneity finite element cell model for the mechanics and fatigueanalysis. Through the previous method, obtaining different hole defect characteristics(porosity, hole position distribution, the hole distribution characteristics and the characteristics of the morphology and distribution of hole defect interaction) of thedog bone type test bar and the long strip and studied the dog bone type test bar underthe condition of the tension and the long strip under the condition of bending theinfluence law of mechanical propertiesand fatigue life.The end of this article takes the arm casting as an example, which use the finiteelement mesh model and defect message map superposition method, the casting holedefect on the casting itself grid model to the structural analysis software, thestructural analysis model is a model with casting defects, and make the results morein line with the actual situation. The use of the method to optimize the structure ofcastings and process design, enhancing casting reliability has the very good guidancesignificance.