Study On Lateral Compression Pressing Of Tin Bronze For Continuous Extrusion

As a new plastic processing technology, the continuous extrusion forming technics has more advantages such as high productivity, low energy-consuming, good quality of product and so on, especially adaptable for the products with large dimension, high intensity and extra requirement of length. Because of its superiority over the traditional extusion technics, so it is widely used in the production. Tin bronze is of high intensity, excellent elasticity, corrosion-resistant, wear-resisting, diamagnetic, good processability, it becomes the most widely used, the most important and most economy copper alloy currently.In order to demonstration the feasibility of tin bronze alloys in continuous extrusion processing, According to the principle of continuous extrusion and lateral extrusion's molding and process characteristics, lateral extrusion die design based on the equal channel angular pressing, and using DEFORM numerical simulation software to simulate the equal channel angular pressing process. Find a feasible initial temperature for extrusion by equal channel angular pressing, Based on the continuous extrusion production conditions, do the high-temperature tensile test in the temperature range for tin-bronze QSn6.5-0.1. Find the temperature that tin bronze alloys below the tensile strength of copper at room temperature strength and good plasticity, which provided theory basis for the establishment of continuous extrusion technology.The main job of this thesis including the following four parts:1. Using Shimadzu high-temperature tensile test machine, do the high-temperature tensile test with standard specimenin, obtained tensile curve, tensile strength and yield strength under the experimental conditions in the 400 ~ 800℃.2. The establishment of the numerical simulation of material model for tin bronze alloys equal channel angular pressing, analysis process of metal flow, temperature distribution and stress distribution, impact of friction coefficient, dead zones were also discussed.3. In the hydraulic machine, do equal channel angular pressing experiment with tin-bronze (QSn6.5-0.1)Ф12x80mm, in the temperature range of 200~600℃, interval is 100℃,measured by the table and squeeze the pressure changes, and analysis of organizations.Studied the surface quality, squeezing pressure on the relationship as temperature at different temperature conditions.4. Continuous extrusion experiment done with the continuous extrusion machine TLG250, in the preheating temperature690～710℃and extruder speed 5rpm, fully preheated mold cavity, initial examinations using the feasibility of continuous extrusion process with the tin bronze QSn6.5-0.1.