Papers by Keyword: Solidification Simulation

Abstract: Casting simulation packages are used to check a design for its castability. A better starting design should need fewer simulation cycles to arrive at a defect-free component thus cutting computation and manpower costs. Quantitative design of the feeding system is done by an analysis of the solidification pattern of the 3D model of the cast component. A clustering algorithm uses the solidification time/temperature data from the simulation to divide the casting into 3D feeding sections. The sections are created by following hotspots surrounded by areas of decreasing solidification time. Feeders are built by the feeder design module of AutoCAST casting design software. The initial simulation as well as the efficacy of the rigging is tested through the advanced simulation module FLOW+ of AutoCAST X. An industrial case study illustrates the software pipeline in a virtual foundry trial.

Abstract: The calibre of low pressure casting (LPC) process in meeting the demands for improved quality and aesthetics for thin walled components has been widely accepted in casting industries. In spite of numerous advantages, the process is still being used very less to its potential. The basic reason has been the difficulty in determining various processing parameters associated which can be circumvented effectively by numerical simulation. In the present work, the commercial CFD code FLOW 3D^TM, has been used to simulate the mould filling and solidification during the LPC process.

Abstract: The numerical simulation of temperature gradient in the solidification process for large bushing castings of zinc-base alloy was made with HUAZHU CAE/Inte-CAST10.0 software in this paper. Tendency and the position of shrinkage were predicted,and the effect of cooling water rate and cooling time on temperature gradient and shrinkage during the molten metal solidification was discussed. The results show that:seting chilled iron at bottom of bearing bush and using water-cooling metal core in inner cavity of casting simultaneously, can eliminated shrinkage hole and porosity.

Abstract: The numerical solidification simulation for gear ring steel casting has been made, and the location and reasons forming casting defects have been predicted by HUAZHU CAE software. Simulating result shows that the directional solidification and efficient feeding were maintained and the casting perfects can be realized by means of the computer simulation optimizing technological and rationally design of gating system, insulated risers, iron chill and compensating efficiently. After magnetic particle detection and ultrasonic inspection, the properties and microstructure of the Gear ring steel casting are in accord with the international standard.

Abstract: Plate fracture is a defective fracture structure in nodular cast iron that can be found especially in the transition area of feeder, feeder neck and the cast part itself. It occurs rather spontaneously due to the fact that the exact reason for it is still unknown. The microstructure of the casting in the area of plate fracture comprises aligned graphite nodules in combination with a pronounced dendritic microstructure as characteristical features. A series of casting trials was performed in which plate like samples were produced. It could be shown by means of metallographic investigation of these samples in combination with the simulation of the solidification that specific local conditions during the solidification are the metallurgical reasons for the appearance of plate fracture. These specific conditions were the local temperature gradient and the velocity of the liquid/solid interface.

Abstract: Calculated phase diagram reveals important phase details for a new type muti-component magnesium alloy. Isothermal sections at 25°C of Mg-Ca-Sr, , Mg-2.74Al-Ca-Sr, Mg-2.74Al-0.79Zn-Ca-Sr system in the Mg-rich region were calculated using CALPHAD method, Thermo-Calc software and Mg-Al-Zn-Ca-Sr quinary database. The equilibrium phase composition in the Mg-rich region was analyzed. The equilibrium phases and solidification process of Mg-2.74Al-0.79Zn-0.68Ca-0.03Sr quinary alloy was calculated. The calculation results were consistent with the experimental results of SEM-EDX analysis and DSC spectrum. The solidification process of Mg-2.74Al-0.79Zn-0.68Ca-0.03Sr quinary alloy is as follow : α-Mg precipitates at 621°C, secondary phase C15-Al2(Ca, Sr) and Gamma-Mg17Al12 precipitate at around 520°C and 160°C in sequence, A4B-(Al4Ca,Al4Sr) may precipitate at around 460°C.

Abstract: The solidification process, the formation mechanism and distribution law of microporosity of the ball milling machine head cover made by SVEDALA corporation of USA were simulated by computer. The Solidworks software was used to generate three-dimensional model of cast parts and the Hua-casting software was employed to simulate the casting process. The simulated results show that significant microporosity was found in the middle of two casting heads and at the place of gudgeon journal because of insufficient chilling degree. The processing rationality was judged through the computer-aided technology, by which some drawbacks of the traditional process were overcome and the process design quality was improved.

Abstract: The numerical solidification simulation for oceangoing freighter rudder horn steel casting has been made and the location and reasons forming casting defects have been predicted by HUAZHU CAE software. Simulating result shows that the casting perfects can be realized by means of the technological optimization and rationally assembling gating system, risers and iron chill. After magnetic particle detection and ultrasonic inspection, the properties and microstructure of the oceangoing freighter rudder horn steel casting are in accord with the standard of USA, Germany and Japan.

Abstract: The silicon-based aluminum casting alloy and 2 different types of gate designs were used to investigate experimentally the fabrication feasibility of sound thin-wall case casting by diecasting process. While split type gate design had no defect, tangential type gate design resulted in cracks in the all obtained specimens. Electrolytic Oxide (PEO) coating was performed as a surface treatment process. Before the PEO coating treatments some die cast specimens were heat treated at the temperature of 323K and N2 atmosphere for 1hr to evaluate the effect of heat treatment. The result showed that hardness was improved after PEO coating, however, the effect of heat treatment was not significant.