Research On The Edge Chipping Mechanic And Experiment Of Engineering Ceramic With Rotary Ultrasonic Grinding

The increasingly widespread application of engineering ceramics led to the rapid development of processing technologies. Rotary ultrasonic grinding has become one processing technology widely used in the processing field of engineering ceramics. However,with its high hardness and brittle, engineering ceramic materials face with many processing quality issues different from other materials in the process, such as edge chipping. In the processing of engineering ceramics parts, rotary ultrasonic grinding has higher processing efficiency and accuracy, deeper working depth as well as smaller tool wear than that of conventional grinding, but it still doesn’t completely avoid edge chipping problems. This paper treats the edge chipping of engineering ceramic in rotating ultrasound grinding machining as the research object. Combined with the process experments, the basic fracture dynamics theory and extended limited element method have been used to study the formation mechanism of edge chipping and its control. The main contents are as follows:Firstly, the formation mechanism of edge chipping for rotary ultrasonic grinding is studied. With anlysis for three types of edge chipping in engineering ceramic machining, the internal edge chipping is researched and the motion characteristics of grain in the surface of diamond tool are anlysed. Based on the contact area of the single grain and material, the mathematical model of grinding forces is establisred. The crack formation and propagation under vibration loading conditions is analysed with dynamic fracture mechanics.Secondly, the formation mechanism of edge chipping with rotary ultrasonic grinding engineering is valided by extended finite element simulation. According to the extended finite element theory, the module of extended finite element in ABAQUS is used to simulate the formation and propagation of any crack in the processing of engineering ceramic. The forming process of edge chipping, the stress in cracks elements and the force in grinding contact area are anlysed.Thirdly, the evaluation of edge chipping is proposed. The geometrical characteristics of edge chipping are observated. The random distribution of edge chipping size is found. The evaluation model and parameters of edge chipping size are established.Finally, the investigation of edge chipping control is carried out with process experiments. According to the process paramaters deterined by the anlysis of the formation mechanism of edge chipping with rotary ultrasonic grinding,the orthogonal test method is arranged to the process experiments. The effects of the process paramaters on the edge chipping are analysed. The process paramatrers of the smallest edge chipping in the given paramaters is identified to contol the edge chipping in machining of Engineering Ceramics.This paper is presented the problem of edge chipping with rotary ultrasonic grinding.The formation mechanism,evaluation and control of edge chipping are studied. Some refences are provided for actual machining of engineering ceramics to reduce or avoid edge chipping.