无铅环保黄铜研究新进展  

Recent Progress in Lead-free Environmentally-friendly Brasses

作　　者：杨超[1,3,4,5] 陶鲭驰 丁言飞 YANG Chao;TAO Qingchi;DING Yanfei(National Engineering Research Center of Near-net-shape Forming for Metallic Materials, South China University of Technology, Guangzhou 510640;Guangdong Huayi Plumbing Fittings Industry Co., Ltd., Jiangmen 529321)

机构地区：[1]华南理工大学国家金属材料近净成形工程技术研究中心,广州510640 [2]广东华艺卫浴实业有限公司,江门529321 [3]中国材料研究学会青年工作委员会 [4]中国金属学会非晶合金分会 [5]美国矿物与金属材料学会

出　　处：《材料导报》2019年第13期2109-2118,共10页Materials Reports

基　　金：广东省应用型科技研发专项重大项目(2016B090931002);广东省公益研究与能力建设专项资金项目(2014A010105020)~~

摘　　要：由于优异的力学性能、耐蚀性能、铸造性能和成形性能,黄铜被广泛应用于卫浴、电工电气、装备制造等诸多产业。通常,黄铜中需加入约3%(质量分数)Pb来改善其切削加工性能。Pb在Cu-Zn合金中以独立相存在,由于Pb质软、脆性大且熔点低,可发挥断屑、润滑和降温作用,从而改善黄铜的切削性能。然而,Pb属于有毒元素,在其生产、加工和使用过程中均会造成环境污染。尤其是当铅黄铜用于与水环境接触的产品时,Pb会以离子形式析出溶于水。Pb中毒会损害人体的血液、神经、消化和生殖系统,极大危害人体健康。鉴于此,研发对人体和环境无毒、无害的无铅环保黄铜成为亟待解决的重要课题。根据铅黄铜的易切削机理可知,新型无铅环保黄铜合金要获得优异的切削性能,则其基体上应存在细小弥散的质点,在切削加工时发挥类似Pb质点的断屑作用。按照质点的存在形式,有益于黄铜合金切削性能的元素可分为微量固溶于Cu并与Cu形成共晶、不固溶于Cu但与Cu形成化合物以及部分固溶于Cu且与Cu形成化合物的三类元素。目前,国内外对第一类替代元素中的Bi等元素进行了系统研究,但这些元素资源有限,且大多有毒,使其难以推广应用;对第二类替代元素的研究也取得了一些成果,然而其易氧化烧损或形成有害夹杂,影响材料的制备和加工。针对第三类替代元素来改善黄铜合金的切削性能则开展了大量研究,如以Sb代Pb、以Mg代Pb和以Si代Pb。然而,Sb与Pb一样属于有毒元素;无铅镁黄铜在熔炼过程中易发生吸气、氧化等铸造缺陷,使熔炼工艺复杂。Si的锌当量系数较大,且资源丰富,无毒害作用,通过调控其含量易于调控无铅硅黄铜的组织结构,且硅黄铜熔炼工艺简单,有望彻底实现黄铜合金“无铅化”,这对保护人体健康与生态环境、节约资源均有积极意义,实现了绿色制造。本�Due to excelle nt mecha ni cal properties, corrosi on resista nee, cast ing properties and formability, brasses alloys are widely used in many in dustries such as san itary ware, electro nic product and equipme nt manu facturi ng. Gen erally, 3wt% Pb is added in to brasses alloys to improve their cutting performance. As a soft and brittle phase with relative low melting point, Pb acts as a separate phase in the Cu-Zn binary alloy, which can play roles of chip breaking, lubrication and cooling, and thus improve the cutting performance of brasses alloys. However, Pb is a toxic element and can cause environmental pollution during its production, processing and usage processes. Especially, when lead brasses are used as products contacting with water environment, Pb ions are easily precipitated from the matrix. Lead poisoning can damage the blood, nerves, digestion and reproductive systems of the human body. On this account, the development of lead-free environmentally-friendly brasses becomes an urgent and significant problem. According to the easy-cutting mechanism of lead brasses, in order to obtain excellent cutting performance, new lead-free environmentallyfriendly brasses alloys should have dispersed fine particles in the matrix, which can play a role of chip breaking like Pb particles during cutting processing. According to the existing modes of the particles, the elements beneficial to the cutting performance of brasses alloys can be classified into three types, minor solid-soluble ones in Cu that can form eutectics with Cu, insoluble ones in Cu that can form compounds with Cu, and partial solid-soluble ones in Cu that can form compounds with Cu. Currently, systematic researches have been carried out on the first type of substitute elements such as Bi. However, these elements are of limited resources and are mostly toxic. Some research results have been obtained on the second type of substitute elements, which are easily oxidized and formed harmful inclusions, thus increasing the difficulty in the preparation

关 键 词：无铅黄铜 锌当量 综合性能 切削性能 

分 类 号：TG146.11[一般工业技术—材料科学与工程]