【作者】 刘辉；

【导师】 于恩林；

【作者基本信息】 燕山大学 ， 机械设计及理论， 2006， 硕士

【摘要】 钎杆用中空钢,简称“钎钢”,截面以正六角形和圆形为主,因此本文以正六角形钎杆用中空钢为研究对象。目前国内生产钎钢的方法主要是热穿-热拔的方法,与热穿-热拔的方法相比较,热穿-热轧生产的中空钢寿命较高,生产效率也较高,因此具有广阔的发展前景。以前,大多学者关于钎杆的研究多集中在钎杆使用过程中应力、应变状态分析、寿命评估、热处理工艺、选材方面,对钎杆用中空钢的轧制过程的研究很少,且都是采用实验和定性分析的方法,尚未见到关于轧制工艺参数和管坯尺寸对成品质量影响定量分析的报道。钎杆用正六角中空钢的轧制过程是最复杂的弹塑性变形过程之一,它涉及到几何、材料、边界条件非线性,同时包含多个物理场的耦合。随着计算机数值模拟技术的发展,更为精确地研究轧制中轧件的变形行为成为可能。本文将采用三维弹塑性有限元法模拟钎杆用中空钢轧制过程,试图找出轧制工艺参数和管坯尺寸对成品的影响规律。本文首先调查了钎杆用中空钢的国内外研究状况;系统阐述了三维弹塑性有限元基本理论,给出了有限元法模拟钎杆用中空钢轧制过程的操作要点;针对不同的轧制工艺参数和管坯尺寸轧制过程,采用有限元分析软件ABAQUS进行了数值模拟,分析了钎钢轧制中轧件金属的变形特征,得到了不同轧制工艺参数和管坯尺寸对成品尺寸影响的规律;最后以铅为材料,对钎杆用中空钢的轧制过程进行了实验研究,分析了管坯尺寸对成品外形的影响,并与数值模拟结果进行了对比,二者取得了较好的吻合,从而验证了三维弹塑性有限元法计算结果的正确性和可靠性。更多还原

【Abstract】 Hollow drill steels which act as drilling steel rods are named rock drillsteels for short. Because their cross sections are almost equilateral hexagons,the equilateral hexagons rock drill steels are regarded as my research objects.Nowadays, the hot piercing and hot stretching method is the main method ofprocessing rock drill steels in our country. In comparison with the hot piercingand hot stretching method, the hot piercing and hot rolling method is morepromising, because the method is more efficient and their finished products’life-span is longer.In the past, research about rock drill steels were mainly converged instrain and stress in work、life-span estimate、hot treatment technics as well asthe choice of material. Few people researched rock drill steels about theprocess of rolling and they often adopted experimental or qualitative methods.Until now I haven’t found the news of how rolling technics variables and thetube billets’ dimension influence the finished products’ figure quantitively. Therolling of rock drill steel is one of the most complex deformation processes,which includes the non-linear of material、geometry、boundary conditions andseveral fields coupling. Modern computer modeling technologies allow toperform more accurate description of material flow behavior of workpiece inrolling. The major effort of this study is to simulate the rock drill steel rollingprocess by using three-dimensional elastic-plastic FEM with the intention tofind the relationship between the technics variables of rolling、the dimension oftube billets and the shape of the finished products.In this work, the historical research on the rock drill steel is reviewed atfirst. The basic theory of elastic-plastic FEM, as well as detailed operationprocedures, is given. Then, rock drill steels rolling processes with different rollpass variable and tube billets’ dimension have been simulated by using three –dimensional finite element code-ABAQUS. The deformation characteristics ofrolled rock drill steels and the relationships between the variables of rollingtechnics、the dimension of tube billets and the shape of finished products areanalyzed. Finally, to validate the computational values, rock drill steels rollingexperiments were carried out by using lead specimens at the experimental Millof Yanshan University. The relations between the dimension of tube billets andthe shape of finished products are investigated and are compared with thecomputational results. It indicates that they meet each other quite well and givethe same conclusions.更多还原