1. 汇报安排

·题目：参加ICSV23国际会议总结报告会

·时间：2016年7月19日19:00-20:00

·地点：机械学院第一会议室

·报告人：博1217班-孟德安、博1321班-朱成成

2. 参加国际会议信息

·会议名称：ICSV23 (The 23rd International Congress on Sound and Vibration)

·会议时间：10-14 July 2016

·会议地点：雅典，希腊

·会议简介：第23届国际声学与振动会议（ICSV23，The 23rd International Congress on Sound and Vibration）是由国际声与振动学会IIAV发起组织的声学与振动研究方面的系列国际学术会议，从1994年开始，每年举行一次，迄今已举办了23届，每届会议的参加人数在400~800人之间，同时会议还展出声学与振动研究方面最新的仪器设备产品和技术，是振动领域影响力最为广泛的学术会议，具有很高的国际声誉。

·会议交流工作：

Presentation –The Effect of Superimposed Low-frequency Vibration on Tensile Deformation of

Low-carbon Steel.（孟德安）

Presentation – The optimization of several technological parameters of ultrasonic vibration aided flow-forming.（朱成成）

3. 参会论文信息

·论文标题：The Effect of Superimposed Low-frequency Vibration on Tensile Deformation of

Low-carbon Steel

·作者：孟德安，赵升吨，朱成成

·摘要：It is well known that ultrasonic vibration can lead to significant load reduction in metal forming which is called acoustic softening and this phenomenon has been widely used in micro/meso forming. Recently, we found low-frequency mechanical vibration with micro-amplitude also had the same effect. Compared with the ultrasonic vibration, mechanical vibration is easier to obtain large force. In this study, tensile deformation of low–carbon steel assisted by low-frequency mechanical vibration with different amplitudes and the contributing mechanisms were investigated. The effects of mechanical vibration decreasing forming stress were analyzed and discussed. In addition, a modeling framework for the vibration plasticity was proposed based on the thermal activation theory. Results show that the reduction of the stress is proportional to vibration amplitude, and the deformed materials appear to permanent softening due to mechanical vibration. The findings of this study confirmed the significant effects of mechanical vibration on metal forming and provide a basis to understanding to vibration-assisted forming.

·论文标题：The optimization of several technological parameters of ultrasonic vibration aided flow-forming

·作者：朱成成，赵升吨，张超，孟德安

·摘要：When using the flow-forming method to manufacture tubes which have big diameter or thick wall, the spinning power will be very large. Too big spinning power leads destabilization and other problems. As we all know, ultrasonic vibration could reduce the power in metal forming process, so the ultrasonic vibration aided flow-forming has been put out. The effect of ultrasonic vibration in this method is complicated, and some studies use experiment or general FEM to find metal flow characters and so on at present . Rollers feed speed and the amplitude of ultrasonic vibration are important parameters in this forming process, but there are few studies on optimization problem under given conditions. We used the finite element software ABAQUS to analyze this kind flow-forming process. By using different amplitudes of ultrasonic vibration and feed speed of spinning rollers, both positive and negative flow forming process was simulated. According to the simulation result, the ultrasonic vibration could effective reduce flow-forming power. With the amplitude of ultrasonic vibration increasing, the material is easier to shape. Otherwise, with the feed speed improving, the forming power will be bigger and bigger. Depend on the simulation result, a set of conditional constraint optimal equations were built to get the best optimal combination of process parameters. This study confirmed the effect of ultrasonic vibration aided flow-forming in forming force side, and found a way to determined technological parameters.

欢迎有兴趣的同学届时前来交流。