日本无铬化处理热镀锌彩钢板的开发厂家
无铬化处理热镀锌彩钢板的生产厂家Superdyma是一种在锌中添加Al、Mg、Si的合金化（zn-11al3mg-0.2si）高耐蚀性的热镀锌钢板。近年来，由于环保意识的提高，首先在家电领域推广无铬产品，在建材产品方面，对无铬产品的要求也越来越高。根据日本国土交通省发布的公共建筑工程标准，2016年无铬可作为建材产品使用。在这种背景下，新日铁住金公司开发了多种适用于超动态的无铬后处理膜，以满足环保的新要求。
Superdyma是一种在合金涂层上附加特殊处理层的钢板。涂层结构如图1所示。特殊处理层是在具有腐蚀因子屏蔽功能的特种膜上加入缓蚀剂的处理层，既具有腐蚀因子屏蔽功能，又具有自愈功能，可替代铬酸盐膜。根据涂层钢板的不同使用条件，对无铬后处理涂层的无机/有机组分和缓蚀剂组分进行了优化，研制出两种无铬后处理涂层：一种是与传统的耐蚀性相同的QN型蒙皮膜铬酸盐涂层，主要成分为无机物；另一种是qfk型膜，具有优异的耐蚀性和加工性能，主要成分为有机物。
表1所示为未经镀铬处理的漆膜性能试验用钢板的状况。原板为superdyma（涂布量为90g/m2）。用QN和qfk分别对原板进行无铬处理。试验采用传统的铬酸盐后处理钢板作为对比钢板。
2.1耐腐蚀性
将试样端部封严，用JISZ2371《盐雾试验》对试样的平面部分进行腐蚀试验，并根据白锈面积评价其耐蚀性。另外，在公孤岛进行了室外暴露试验。将试样的端部和背面密封，进行暴露腐蚀试验，试样朝南倾斜45度。根据白锈面积比评价其耐蚀性。
2.2润滑
动摩擦系数是判断钢板成形性的指标之一。用heidon-14型动态摩擦系数测试仪测定了钢板的动摩擦系数。滑动件为直径10mm，载荷为1.0N的不锈钢球，钢球滑动速度为150mm/min，根据钢球确定动摩擦系数。
此外，为了评价钢板在冲压过程中的滑动性能，测量了钢板拉伸试验中的动摩擦系数。试验钢板采用SKD11制作的平面模具夹紧，接触面积为30mm×25mm。夹紧力为0.5kn。以200mm/min的速度拉制试样，根据拉拔工艺确定摩擦系数。
2.3导电性
测量了试验材料的层间电阻和接触电阻（接地）。按jisc2550标准测量层间电阻，测试电压为0.5V，测试压力为2n/mm2。接触电阻测量方法为四探针法。
Superdyma is an alloying (zn-11al3mg-0.2si) hot-dip galvanized steel sheet with high corrosion resistance and alloying (zn-11al3mg-0.2si) by adding Al, Mg and Si to Zn. In recent years, due to the improvement of environmental protection awareness, first
of all in the field of home appliances to promote chrome free products, in building materials products, the requirements of chromium free products are also increasing. According to the public building engineering standards issued by the Ministry of
land and transportation of Japan, chromium free may be used as building material products in 2016. In this context, Nippon Steel Sumikin has developed a variety of chrome free post-treatment films suitable for superdyma to meet the new requirements
of environmental protection.
1. Structure of chromium free post treated galvanized steel sheet
Superdyma s a kind of steel plate with special treatment layer attached on the alloyed coating. The coating structure is shown in Fig. 1. The special treatment layer is a treatment
layer with corrosion inhibitor added to the special film with corrosion factor shielding function, so it has both corrosion factor shielding function and self-healing function, and can replace chromate film. According to the different service conditions
of the coated steel plate, the inorganic / organic components and corrosion inhibitor components of the chrome free post-treatment coating were optimized, and two kinds of non chrome post-treatment coatings were developed: one was QN type skin film with
the same corrosion resistance as the traditional chromate coating, and the main component was inorganic compounds; The other is qfk type film with excellent corrosion resistance and processability and mainly composed of organic compounds.
2. Test
method for properties of chrome free aftertreatment film
Table 1 shows the condition of the steel plate used for the film performance test without chrome treatment. The original plate is superdyma (the coating amount is 90g / m2). The original plate
is treated by QN and qfk without chromium respectively. The traditional chromate post-treatment steel plate is used as the contrast steel plate for test.
2.1 corrosion resistance
The end of the sample was sealed, and the corrosion test was
carried out on the plane part of the sample by salt spray test (JISZ2371), and the corrosion resistance was evaluated according to the area of white rust. In addition, outdoor exposure test was conducted in gonggu island. The end and back of the sample
were sealed, and the exposed corrosion test was carried out with the specimen facing south and inclining 45 degrees. The corrosion resistance was evaluated according to the area ratio of white rust.
2.2 lubrication
The dynamic friction coefficient is one of the indexes to judge the formability of steel plate. The dynamic friction coefficient of steel plate was measured by heidon-14 dynamic friction coefficient tester. The sliding piece
is a stainless steel ball with a diameter of 10 mm and a load of 1.0 n. The sliding speed of steel ball is 150 mm / min, and the dynamic friction coefficient shall be determined according to the steel ball.
In addition, in order to evaluate the
sliding property of the steel plate plane during die stamping, the dynamic friction coefficient in the steel plate drawing test was measured. The test steel plate was clamped with a plane die made of SKD11 and the contact area was 30mm × 25mm. The clamping
force was 0.5kn. The sample is drawn at the speed of 200 mm / min, and the friction coefficient is determined according to the drawing process.
2.3 conductivity
The interlayer resistance and contact resistance (grounding) of the test materials
were measured. The interlayer resistance was measured according to jisc2550, the test voltage was 0.5V, and the test pressure was 2n / mm2. The contact resistance measurement method is four probe method.
