酸堿值
磷化液里產生磷化膜的鐵離子濃度太低,那么所要求的酸堿值越大。相反來講,鐵離子含量越高,酸堿性越少。利用酸堿度控制高溫錳系磷化液的游離酸很簡單,例如酸堿性是1那么游離酸就是0.1。探索酸堿性對錳系磷化液的反應,結果顯示,硝酸的含量0.5時,當酸堿值在5表示有鈍化反應,產生鈍化膜。酸堿性是2時,產生的膜是磷化膜和鈍化膜的綜合體,硝酸含量越大,磷化膜區域越大,當酸堿性是3的時候,就沒有磷化膜形成了,所以高溫錳系磷化液的酸堿性為2.5*好。
溫度
對于所生產的磷化液,磷化是否能成膜,溫度也是很重要的一個原因,溫度對磷化膜和磷化效率的影響非常明顯。適合的溫度不僅能促使鐵在陽極區域的融化和磷酸鐵反應,縮短磷化膜形成的時間。還能激活能力低的地方,形成活化中心使晶體數量快速增加,形成結晶的速度加快,在反應的時候又有大批的中心點生成,晶體還沒完全長大,又有新的晶體開始產生。結晶密度大,磷化膜細致緊密,磷化膜的厚度增厚,抗腐蝕的能力增強,溫度太低形成磷化膜的磷化液含量達不到,不能生產完整的磷化膜。溫度太大,導致可溶解型的成分的分離,分離出大量的鋅離子和磷酸跟離子,使得大量的磷酸鹽快速分離,產生大量沉渣,失去原來的動態平衡,常溫磷化液溫度太高時,不僅影響酸比的變動,而且反應速度太快,磷化膜結晶粗大,空隙率太大,產生磷化渣的超重量磷化膜,腐蝕性低,影響涂層的光澤,并使槽液穩定性變差。
ph Phosphating of phosphating film in liquid iron ion concentration is too low, so the required ph. Instead, the iron ions content is higher, the less acid alkaline. Use high manganese series phosphating solution of free acid ph control is very simple, such as acid, alkali is 1 then free acid is 0.1. Explore acid alkaline reaction of manganese series phosphating solution, results showed that nitrate content of 0.5, when ph 5 said passivation reaction, passivation membrane. Acid alkali is 2, the film is a complex of phosphating film and passivation film, the nitrate content, the greater the phosphating film area is larger, when the acid alkali is 3, phosphating film formed, so the department of high manganese phosphating liquid acid alkaline 2.5 is best. The temperature Whether can for the production of the phosphating liquid and phosphating film, temperature is an important one of the reasons, and temperature on the efficiency of the phosphating film and phosphating effect is very obvious. Suitable temperature can not only make the iron in the melting of the anode region and iron phosphate reaction, shorten the time of the phosphating film formation. Can also activate a region of low ability, forming the activation center the crystal quantity increase quickly, and form the crystallization speed, at the time of reaction and generation, the center of the large crystal haven't fully grown, and have new crystals begin to produce. Meticulous crystallization density, phosphating film closely, thickening of the thickness of the phosphating film, enhanced corrosion resistance, low temperature phosphating film formed of the phosphating liquid content of less than, can't complete phosphating film production. Temperature is too large, which leads to the separation of components can be dissolved, separating out large amounts of zinc ion and phosphate ion, makes a lot of phosphate rapid separation, produce large amounts of sediment, losing the original dynamic equilibrium, liquid at room temperature is too high, not only affect the change of acid ratio, and reaction speed too fast, the phosphating film crystallization bulky, void ratio is too large, produce phosphating phosphating film residue super weight, corrosion resistance is low, influence the luster of the coating, and bath stability. |
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