Bakırın kimyasal işlenmesi

Abstract

Keywords

• Kimyasal işleme, bakır, aşındırma derinliği, yüzey pürüzlülüğü

Chemical machining of copper

Abstract

Copper and its alloys are major engineering materials that is extensively used particularly in electronics industry due to their eletrical properties. The importance of these materials attracted many researches for investigating various production methods. Chemical machining is one of them. This machining process is widely used in various industries to produce complex components from flat materials. The process is called controlled corrosion operation of workpiece material in acidic or alkaline environment. The major advantage of chemical machining is the manufacture of high precision parts in a short machining time with low production cost. Moreover, the process does not need a special tool and product parts are burr free. However, chemical machining is not environmentally friendly machining process due to chemical etchants which have advers effect on environment. This problem is almost overcomed by using regeneration of waste etchant and recovery of etched material simultaniously. The chemical machining of copper is vital process in the electronics industry. It is a major production step in the manufacture of printed circuit boards. Various chemical etchants can be used to shape in chemical machining of copper, one of them is cupric chloride (CuCl2). The advantages of this etchant over other etchants are numerous; high etch rate, compatible with etching maskant, cost effective, possibility of etched material recovery and full regeneration of waste etchant. These properties make the etchant possible the most environmetally friendly chemical solution in the chemical machining of copper.These properties make this etchant more attractive in case of chemical machining of copper. In the present study, chemical machining of copper with CuCl2 was examined. The selected material was 99.9% pure copper (DIN EN 1652). The experimental study was completed in beaker as immerse chemical machining method. The selected etchant concentrations and temperatures were 2.04, 2.33 and 2.65 Mol; and 30°C, 50°C and 70°C. Most of the parameters were related to literature survey, but the highest temperature (70°C) was not widely used. The prepared etchant solution was placed on hot plate with magnetic stirrer. The chemical machining temperature was kept at ± 2°C. The total machining time was 20 mins and each measurement of thickness and surface roughness were taken at every 5 mins. The aim of this study was to examine the effects of selected etchant concentration and temperature on depth of etch and surface roughness in chemical machining of copper. It was concluded that etchant concentration is important factor on depth of etch, higher etchant concentration increased depth of etch. Surface roughnes was affected by etchant concentration and temperature.

Keywords

• Chemical machining, copper, depth of etch, surface roughness.