7Cr7Mo2V2Si,代号LD，***初是针对冷镦模具而研制的。其碳含量低于G.Steven推荐的“平衡碳”规律，使钢在具有高硬度的同时，又具有较好韧性；加入Cr、Mo、V元素，有利于二次硬化，保证钢具有较高的硬度、强度和良好的耐磨性；加入一定量的Si，以强化基体，提高回火稳定性成份：C:0.70-0.80SI:070-1.20MN:≤0.50P:≤0.030CR:6.50-7.00Mo:2.00-2.50V:1.70-2.20用途：LD钢已被广泛应用于制造冷锻、冷冲、冷压、冷弯等随冲击、弯曲应力较大，又要求耐磨损的各类冷作模具。vardelta=0.2;varcollection;varcloseB=false;functionfloaters(){this.items=[];this.addItem=function(id,x,y,content){document.write(''+content+'');varnewItem={};newItem.object=document.getElementById(id);newItem.x=x;newItem.y=y;this.items[this.items.length]=newItem;}this.play=function(){collection=this.itemssetInterval('play()',30);}}functionplay(){if(screen.width0?1:-1)*Math.ceil(Math.abs(dx));followObj.style.left=followObj.offsetLeft+dx;}if(followObj.offsetTop!=(document.body.scrollTop+followObj_y)){vardy=(document.body.scrollTop+followObj_y-followObj.offsetTop)*delta;dy=(dy>0?1:-1)*Math.ceil(Math.abs(dy));followObj.style.top=followObj.offsetTop+dy;}followObj.style.display='';}}functioncloseBanner(){closeB=true;return;}vartheFloaters=newfloaters();//theFloaters.addItem('followDiv1','document.body.clientWidth-105',160,'关闭');theFloaters.play();)