Research On High Velocity Compaction Mechanism And Numerical Simulation Of Iron Based Powder

A key indicator of the consistency of the impact molding is the inherent properties of iron based powder metallurgy products aperture.The low density of conventionally pressed compacts limits the improvement of part performance.The pursuit of high-performance iron based products is a core issue in the field of powder metallurgy.As compared to traditional compaction,high velocity compaction(HVC)produces high-density,high-performance,high-precision,and low-cost components,effectively addressing the core problem.The mechanism of densification and numerical simulation of high velocity compaction of iron based powders was investigated in this paper.The following is a list of the relevant jobs.1)The characteristics of high velocity compaction have been studied.and it has been noted that HVC has the characteristics of high compaction speed,large impact energy,high forming density,and uniform distribution.The mechanism of densification can be studied by looking into it.The transfer of compaction load is discovered to be a dynamic operation,and the green body's efficiency can be continuously enhanced by producing stress waves.According to the particle flow and deformation state,the molding process is divided into five stages:powder filling,particle rearrangement,extrusion deformation,crushing compaction,and elastic aftereffect.Different methods are used to analyze the influence of each stage on the performance of the compact.2)MSC.MARC software was used to simulate the HVC process from two levels of macroscopic overall and mesoscopic particles.The effects of five factors,namely the compaction speed,sidewall friction coefficient,compaction method,height-diameter ratio,and shape characteristics,on the properties of the green body and particle flow and deformation are discussed.The following are the conclusions:(1)The key factor influencing the density of the green body is compaction speed.The key factors are the wall friction coefficient and the compaction process.The height-diameter ratio has an effect on both distribution density and uniformity.(2)Cylindrical and sleeve compacts have identical density distributions,and the density of the cone-cylinder slope field is specifically stratified.The uniformity of the compact density distribution will deteriorate as sidewall friction increases.(3)Two-way or floating compaction has a greater forming effect than one-way compaction.The compact cannot be built if the aspect ratio is too high,and the green body will be over-pressed if the height-diameter ratio is too small.3)Biaxial compaction power,compaction mode,height-diameter ratio,and the number of compactions four variables combination regimen experimental group samples obtained 8.The success metrics were used to draw conclusions:(1)The density and uniformity of the green body can be improved by increasing the compaction power.Top area>middle area>bottom area is the unidirectional compaction density distribution law.Since the density of floating compaction is distributed as top area>bottom area>middle area,the molding effect of floating compaction is superior to unidirectional compaction.(2)As opposed to single compaction,the secondary compaction's density distribution uniformity is significantly improved;the density and uniformity of the secondary compaction are significantly improved.Green bodies with a low height-to-diameter ratio are preferable to those with a high ratio.The green body's efficiency improves dramatically after sintering.The findings of this analysis indicate that high velocity compaction is a modern technique for producing high-performance parts at a low cost.There are five stages to the compaction process:powder filling,particle rearrangement,extrusion deformation,crushing compaction,and elastic after-effect.Compaction speed,according to the simulation review,is the most important factor influencing the compact's efficiency.Compaction process,sidewall friction coefficient,and height-to-diameter ratio Following the development of a scheme and the study of experimental results,the best possible combination scheme is found.Experiment and simulation effects are almost identical.It offers both theoretical and practical guidance for improving the molding process and component quality.Iron based powder metallurgy;high velocity compaction;formation mechanism;numerical simulation;stage analysis are some of the words used in this article.