A technology for preparing silver tin oxide contact material by powder rolling method

Abstract

The invention discloses a process for preparing a silver tin oxide contact material through a powder rolling method. The process specifically comprises the following steps: rolling mixed powder of silver oxide into a flaky material with thickness of 0.1-0.6 mm through a rolling mill, and carrying out isostatic pressing, sintering and extruding the obtained flaky material to obtain the silver tin oxide contact material; the diameters of rollers of the rolling mill are 60-200 mm, the gap between two rollers is 0.1-0.6 mm, and the rolling speed is 2-10 m / min. According to the process disclosed by the invention, powder rolling technology is introduced into the conventional powder metallurgic method of preparing silver tin oxide, the mixed powder of silver oxide is rolled by the rolling mill to change the simple distribution state of silver particles and tin oxide particles in the conventional powder metallurgic process, and the tin oxide particles are pressed into the silver particle matrix so as to perfect the bonding strength of silver and tin oxide in the material and improve the mechanical and physical properties and electrical properties of the obtained silver tin oxide contact material.

Description

technical field [0001] The invention relates to the field of metal matrix composite materials, in particular to a process for preparing silver tin oxide contact materials by a powder rolling method. Background technique [0002] At present, the process methods for preparing silver tin oxide contact materials can be divided into three categories: powder metallurgy method, chemical method and internal oxidation method, and the internal oxidation method can be subdivided into alloy internal oxidation method and alloy powder pre-oxidation method. The main process route for preparing silver tin oxide series materials by conventional powder metallurgy is: (silver powder + tin oxide powder + additive powder (if any)) powder mixing→isostatic pressing→sintering→extrusion into wire or strip. The advantage of the conventional powder metallurgy method is that the process is simple, and it can produce silver tin oxide series materials with various composition ratios. The powder mixing me...

AI Technical Summary

Problems solved by technology

However, the actual application shows that the high-energy ball milling process has the following disadvantages: (1) In order to achieve a better ball milling effect, a high ball-to-material ratio and a long ball milling time are usually used, so the production efficiency is low; (2) It is easy to appear after ball milling. The phenomenon of powder sticking to the ball makes it difficult to clean the material, resulting in large material loss and high process cost; (3) The abrasive wears seriously under long-term high-energy impact, and it is inevitably mixed into the mixed powder, which affects the purity of the material

Therefore, at present, high-energy ball milling has not been effectively promoted in the production and application of silver tin oxide contact materials in batches.

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