Study On Laser Coupling Bionic Repairing Of Wear Scrapped Non-uniform Microhardness Surface

Due to inevitable wear,every year a large number of equipment was scrapped because of wear failure,which caused a lot of resources wasted.To save resources and improve their life cycles,it needs to repair worn parts.Now in order to achieve circulation economy and energy conservation,the strategic requirement in China is to focus on developing remanufacture engineering.Usually hardness and stress of worn failure surface on discarded parts was non-uniform.Taking worn failure surface of machine tool guide rail retaining quenching layer for example,because the tool rest moved non-uniformly along the rail for a long time,meanwhile micro-structure and micro-hardness of residual quenching layer changes in gradient along thickness,so eventually make hardness of worn failure surface non-uniform.There are two ways to repair it and obtain uniform surface.One is removing residual quenching layer,but it can’t make the size of guide rail meet application requirements,and it also consumes a large amount of manpower.As a result,it would not be considered.The other is to repair hardness non-uniform surface of worn failure for the wear resistance uniformity,which is the research purpose in the paper.Because of the complexity of wear non-uniform conditions,currently it is difficult for single surface repairing technology to make wear resistance of surface uniform.Using bionics ideas and via the wear experiment,the paper found that different bionic coupling models on different hardness partitions had different changing rules of wear resistance.By matching different bionic coupling model on different hardness partition,it would make different hardness partition obtain the different wear resistance gain,therefore it could repair hardness non-uniform surface of worn failure to uniform wear resistance.Consequently,this paper put forward partition to build bionic coupling models to repair wear scrapped non-uniform microhardness surface,which is a breakthrough to repair non-uniform surface for uniform wear resistance.Steps of partition to build bionic coupling models were as follows: 1,According to different hardness,the non-uniform microhardness surface was divided into low hardness region(A region),medium hardness region(B region)and high hardness region(C region);2,different bionic coupling models were matched on different hardness partitions: first to determine the wear-resisting target M,and then based on the matching principle of bionic abrasion uniformity to calculate K1%,K2% and K3% which were respectively theoryreduced percentage of worn height of A,B,C regions;according to influence formulas between bionic coupling models and wear resistance on different hardness partitions,A region matched the bionic coupling model whose reduced percentage of worn height was K1%,B region matched the bionic coupling model whose reduced percentage of worn height was K2%,and C region matched the bionic coupling model whose reduced percentage of worn height was K3%;3,Actual distances of different hardness partitions were fine-tuned.With the change of wear-resisting target M,matched bionic coupling models of different hardness partitions would change.The article gave an example to analyze,namely when wear-resisting target M was 8years,building bionic coupling models were as follows: bionic coupling model of low hardness region was reticulation unit,whose distance range was from 4.91 mm to 6.01mm;bionic coupling model of medium hardness region was striation unit,whose distance range was from 3.83 mm to 4.53mm;bionic coupling model of high hardness region was spot unit,whose distance range was from 2.25 mm to 2.60 mm.Stitching bionic coupling models of different hardness partitions into 5 groups of bionic samples,the wear resistance of different bionic coupling models of 5 groups of bionic samples was the same,which met the purpose of repairing to uniform wear resistance;the wear resistance was 0.051221μm,which differed by 0.041% from theory wear resistance,which noted that it was effective in partition to build bionic coupling models to repair wear scrapped non-uniform microhardness surface.