How to identify collectors'

by:DIgao     2020-06-15
Copper and copper alloy and standardize the classification of copper and copper alloy, China used to according to the classification of colour and lustre, generally divided into four categories: 1, copper: refers to the pure copper, the main variety of multi-layer lock oxygen copper, copper, phosphorus deoxidized copper, silver copper; 2, brass: refers to an alloy of copper and zinc, and copper padlock subdivided into simple brass, brass and complex complex brass and in the third group of yuan named for nickel, brass, silicon brass, etc. ; 3, bronze: refers to the gun except copper and nickel, copper, zinc alloy lock of copper base alloy, the main varieties are tin bronze, aluminum bronze, bronze (special Also known as the high copper alloy) ; 4, cupronickel: refers to the copper nickel alloy; Copper and copper alloy standardization work progress rapidly in our country, the national standard for copper is divided into four categories: based on a standard, including GB5231 - 2001 provides for processing of copper and copper alloy chemical composition and shape of the product; 2. Standard chemical analysis methods, principal component and the provisions of the copper and the alloy chemical analysis method of impurity elements; Three for the physical and chemical properties test method, including the resistance coefficient, ultrasonic testing, eddy current flaw detection, residual stress, dezincification corrosion, oxygen-free copper, fracture, oxygen content regulation methods, such as grain size; Four criteria for the product, including using copper ingot copper cathode, electrician, ingot casting brass, casting bronze ingot, blister copper, copper sulfate, among among beryllium copper alloy, copper alloy, copper concentrate and the copper and alloy processing material standards. China, in addition to the national standards and industry standards and enterprise standards, to meet the needs of product development, supply and demand both sides also agreed on special technical conditions. Copper and copper alloy products around the world are incorporated into the national standards, such as the United States ASTM standard, JIS standard, British BS standard, the German DIN standards, French NF, Russia Γ OCT standards, international standards such as ISO, eu BSEN standards; Standardized work is very important to the national economy development, at the same time also is the summary of the copper production, research, application, so the copper and copper alloy standard in all countries of the world is constantly revised and perfected.
Custom message
Chat Online 编辑模式下无法使用
Chat Online inputting...