成人精品免费高清精品电影,久久久久亚洲vA无码区首,五月天丁香社区精品 超热 99,丁香五月天影院久久18成人精品

中國紫銅加工材按成分可分為：普通紫銅(T1、T2、T3、T4)、無氧銅（TU1、TU2和高純、真空無氧銅）、脫氧銅（TUP、TUMn）、添加少量合金元素的特種銅（砷銅、碲銅、銀銅）四類。紫銅的電導率和熱導率僅次于銀，廣泛用于制作導電、導熱器材。紫銅在大氣、海水和某些非氧化性酸（鹽酸、稀硫酸）、堿、鹽溶液及多種有機酸（醋酸、檸檬酸）中，有良好的耐蝕性，用于化學工業。另外，紫銅有良好的焊接性，可經冷、熱塑性加工制成各種半成品和成品。20世紀70年代，紫銅的產量超過了其他各類銅合金的總產量。

The temperature control function of the air conditioner and the refrigerator is mainly realized by the evaporation and condensation of the copper tube of the heat exchanger. The size and heat transfer performance of heat exchange heat transfer tube determine the efficiency and miniaturization of the whole air conditioner and refrigeration device to a great extent. In these machines, the special-shaped copper tubes with high thermal conductivity are used. With the good processing performance of steel, the heat pipe with inner groove and high fin has been developed and produced recently, which is used to manufacture heat exchanger in air conditioner, refrigerator, chemical industry and waste heat collector. The total heat transfer coefficient of the new heat exchanger can be increased to 2-3 times of that of the common pipe and 1.2-1.3 times of that of the common low fin pipe. It has been used in China and can save 40% of copper, The volume of heat exchanger is reduced by more than 1 / 3.

By analyzing the history and characteristics of copper application and development, it can be concluded that the development of new alloys with new functions and characteristics and the research of new material forming technology are two basic ways to develop new application fields of copper alloy materials and meet the new needs of sustainable development of human society. Based on the traditional copper and its alloy system, the research and development direction of high-performance copper alloy materials at present mainly includes four aspects: high purification, microalloying, complex multi-element alloying and composite material.