安美特 电镀基础知识培训

Atotech (China) Chemicals Ltd.SH 安美特上海青浦分公司PRESENTSELECTROPLATINGTRAINING电镀培训OUTLINE 内容提要♌INTRODUCTION介绍♌ELECTROCHEMISTRY 电化学♌CLEANING & PREPLATE 清洗及预镀♌NICKEL 镍♌Copper 铜♌DECORATIVE CHROMIUM 装饰铬♌TESTING测试♌FILTRATION过滤♌TROUBLE SHOOTING 故障处理WHAT IS ELECTROPLATING ?什么是电镀？THE DEPOSITION OF A METALLICCOATING UPON A NEGATIVELYCHARGED CATHODE BY THEPASSING OF AN ELECTRIC CURRENT 在电流通过时，有金属层沉积在带负电荷的阴极表面.WHAT IS THE PURPOSE ?电镀的目的是什么？♌TO OBTAIN A METALLIC COATING HAVING CERTAIN PROPERTIES SUCH AS HARDNESS, BRIGHTNESS, CORROSION RESISTANCE AND TO REPRODUCE IDENTICAL FORMS IN ELECTROFORMING.♌是为了得到具有某种特性的金属层，如：硬度、光亮度、耐腐性及在电铸方面复制同样的形状.REQUIREMENTS要求♌SOURCE OF DIRECT CURRENT直流电源♌A PLATING TANK电镀槽♌A SOLUTION CONTAINING THE DISSOLVED SALTS OF THE METAL TO BE PLATED含有待镀的可溶性金属盐的溶液♌ANODE( POSITIVE ELECTRODE )阳极（正电极）♌A PREPARED OBJECT -CATHODE ( NEGATIVE ELECTRODE )准备好的待镀工件--阴极（负电极）WHAT IS DIRECT CURRENT ?何为直流电？THE FLOW OF ELECTRONS IN THE SAME DIRECTION BETWEEN POSITIVE ANDNEGATIVE ELECTRODES在正负电极之间电子向同样的方向移动.WHAT IS A PLATING SOLUTION ?电镀液是什么？A CONDUCTING MEDIUM FOR THEMOVEMENT OF METAL IONS INSOLUTION BETWEEN AN ANODE ANDA CATHODE溶液中在阳极与阴极间金属离子移动的导电介质.WHAT IS pH ?什么是pH值？♌THE MEASUREMENT OF ACIDITY OR ALKALINITY用来度量酸碱度的♌ON A SCALE FROM 0 TO 14pH值的范围处于0-14之间♌0 TO 6.9 BEING ACIDIC AND7.1 TO 14 ALKALINE AND 7.0 BEING NEUTRAL.小于7的为酸性，大于7且小于等于14的为碱性，7.0为中性HOW ARE PLATING SOLUTION MAINTAINED ?如何维护电镀液？♌CHEMICAL ANALYSIS OF THE CONSTITUENTS持续的化学分析♌HULL CELL PLATING TESTS赫氏槽电镀测试♌ADDITION OF CHEMICALS添加化学品♌ELIMINATION OF CONTAMINANTS去除污染物♌PERIODIC PURIFICATION定期净化♌REGULAR INSPECTION OF PARTS FOR DEFECTS缺陷/次品的常规检查♌PHYSICAL TESTING物理测试WHAT IS A METAL ION ?什么是金属离子？A METAL ION IS AN ATOM OF A METAL HAVING A POSITIVE ELECTRICAL CHARGE金属离子是带正电荷的金属原子(失去电子)WHAT ARE THE SOURCES OF METAL IONS ?金属离子来自何处？♌METAL SALTS IN PLATING SOLUTION电镀液中的金属盐♌SOLUBLE METAL ANODES可溶性的金属阳极WHAT ARE ANODE BAGS ?什么是阳极袋？ANODE BAGS ARE POROUS MEMBRANES PLACED AROUND ANODES TO COLLECT SLUDGE FORMING ON THE DISSOLVING ANODE 阳极袋是包扎在阳极外面,会将电镀过程中产生的阳极泥收集在袋内的多孔的袋。

Basic ELECTROCHEMISTRY 基本的电化学理论ELECTROCHEMISTRY 电化学Plating Cell 电镀槽Ni++Ni++Cl -Cl -++_Rectifier 整流器ANODE 阳极CATHODE 阴极ANODE 阳极CATHODE REACTIONS 阴极反应Cathode 阴极♌Reduction of ions离子还原反应♌Draw electrons from the external circuit从外部电路中吸收电子♌TYPICAL REACTION 典型的反应Ni++ + 2e-Ni (metal 金属)2H++ 2e-H24H2O + 4e-2H2+ 4(OH)-ANODE REACTIONS 阳极反应Anode 阳极♌Oxidation of metal to ions 金属氧化成阳离子♌Release of electrons to external circuit 将电子释放至外部电路♌TYPICAL REACTION 典型的反应Ni Ni++ + 2e-4OH-O2+ 2H2O + 4e-2H2O O2+ 4H++ 4e-RATE OF CURRENT FLOW 电流速率Ohm’s Law 欧姆定律Amperes安培= Volts 伏特Ohms 欧姆I 电流= E 电压R 电阻Factors 要素Amperes 安培Time 时间Equivalent Weight of Metal 金属当量♌One ampere flowing for one second represents one coulomb. Faraday’ law states that 96,500 coulombs (one Faraday) will deposit one gram equivalent weight of a metal. Equivalent weight is the atomic weight of the metal divided by it’s valence.♌1安培的电流1秒的时间通过的电量等于1库仑。

法拉第定律：1个法拉第即96,500库仑的电量可以沉积1克当量的金属。

克当量是金属的原子量除以它的化合价.weight of metal deposited沉积的金属重量96,500 Coulombs Deposit At. Wt. = grams 96,500库仑的镀层ValenceWEIGHT OF NICKEL PLATED电镀镍的重量KNOWN FACTORS已知的条件Current 电流= 50 amps安培Time 时间= 15 mins分钟原子量At. Wt. Ni = 58.7 Valence = 化合价, 2 价CALCULATION 计算96,500= 45,000X = 13.7 GRAMS 克58.7x grams2CALCULATING THICKNESS FROM WEIGHT从重量计算厚度Thickness = WT1u m=10 -4 cmdensity x area1mil = 25. 4 u m EXAMPLE :wt = 0.136 grams .Density of Ni = 8.9 Area = 4 cm2Thickness =0.1368.9 x 4 Answer = 1.5 milsCURRENT IN CELL电镀槽中的电流Anode阳极-e = cathode阴极+eAnode阳极-e = corrosion溶解-e + Oxygen氧-e Cathode阴极+e = plating所镀金属+e+ hydrogen氢+e The exchange of electrons at the anodeand the cathode or the total flow of currentat each electrode is always equal.电子在阳极和阴极上交换,在阴阳极上流动的电流总是相等的。

DEPOSITION WITH H 2LIBERATION 伴随着氢气释放的沉积NET RESULT 最终的结果1.Cathode Efficiency Reduced 阴极电流效率的降低2.pH Increased pH 值升高Anode 阳极Cathode 阴极Ni +2Ni +22H +H 2PLATING EFFICIENCY ANDTIME OF PLATING电镀效率和电镀时间% Efficiency效率=Actual Ni Plated实际镀的镍X 100Theoretical (Faraday’s Law )理论的（法拉第定律）FACTORS AFFECTING PLATING CURRENT 影响电镀电流的因素♌Hydrogen Liberation ( cathode )氢气释放（阴极）♌Oxygen Liberation ( anode )氧气释放（阳极）♌Polarization极化♌Concentration Polarization ( Diffusion )浓度极化（扩散）♌Hydrogen Overvoltage氢过电位POLARIZATION极化E = IRE = Volts伏特( potential difference电位差)R = Resistance电阻( resistance of solution to the flow of current 溶液对电流的阻抗)I = Current电流( flow of electricity电荷的移动) E = CURRENT电流(I) X RESISTANCE电阻(R) Ep = Change in potential difference due to Polarization from resistance. 由于电阻升高造成的极化,极化导致的电位差的改变.POLARIZATION 极化EI E pR= EIE P= PolarizationCONCENTRATION POLARIZATION浓度极化♌CONCENTRATION OF METAL IONS BUILD ON THE SURFACE OF THE ANODE阳极表面的金属离子浓度♌CONCENTRATION OF THE METAL IONS DECREASE AT THE SURFACE OF THE CATHODE阴极表面的金属离子浓度减少♌CHANGE IN ANODE AND CATHODE FILMS CAUSES POLARIZATION阳极和阴极膜层的改变导致了极化CONCENTRATION POLARIZATION 浓度极化Ni ++Ions ANODE 阳极CATHODE 阴极+++++++++++++++++++ ++ ++ ++ +EFFECT 影响Agitation 打气Temperature 温度氢过电位POLARIZATION DUE TO EVOLUTION OF HYDROGEN UPON A SPECIFIED ELECTRODE SURFACE OR THE EXCESS POTENTIAL ABOVE THE EQUILIBRIUM POTENTIAL REQUIRED TO EVOLVE HYDROGEN AT THE CURRENT DENSITY SPECIFIED.在指定的电极表面上氢气的形成而引起的极化或在某一电流密度下氢的形成所要求的超出平衡电位后的电位.氢过电压FACTORS 要素TYPE OF METAL金属的种类SURFACE ROUGHNESS 表面的粗糙度TYPE OF SOLUTION 溶液的类型CURRENT DENSITY电流密度TEMPERATURE温度HYDROGEN OVERVOLTAGE 氢过电位(1 ma/cm2)♌Zn ♌Sn ♌Cd ♌Cu ♌Ni ♌Ag ♌Au ♌C ♌Pt -0.80 -0.80 -0.80 -0.60 -0.40 -0.30 -0.15 -0.11 0.00ELECTROMOTIVE SERIES电势序列Volts Al3+-1.66 Zn2+-0.76 Cr3+-0.74 Fe2+-0.44 Cd2+ -0.40 Co2+-0.29 Ni2+-0.25 Sn2+ -0.14 Pb2+-0.13Volts H1+0.00 Sb3++0.10 Bi3++0.20 Cu2+ +0.34 Cu1+ +0.52 Rh3++0.80 Ag1++0.80 Pt2++1.20 Au1++1.68ANY QUESTIONS ?有问题吗？CLEANING & PREPLATE 清洗与预镀PURPOSE FOR CLEANING清洗的目的♌TO PROVIDE ADHESION ON THE SUBSEQUENT DEPOSITS保障后续的镀层的结合力.♌TO OBTAIN A HIGH QUALITY FINISH DEPOSIT得到高品质的完美镀层♌TO OBTAIN THE DESIRED PROPERTIES OF THE DEPOSITS镀层具有期望的各种特性.EFFECTS OF IMPROPER CLEANING 不正确清洗的影响♌POOR BONDING TO BASE METAL与基体(素材)金属间差的结合力♌PEELING OF DEPOSIT镀层的起皮♌SKIP PLATE漏镀♌MICRO ROUGHNESS微观粗糙♌PITTING起泡♌POOR CORROSION RESISTANCE差的耐腐性♌CONTAMINATED BATHS污染镀液PRECLEANING OPTIONS预清洗的选择♌MECHANICAL CLEANING 机械清洗WET OR DRY BLASTING 干法喷砂/丸♌SOLVENT CLEANING 溶剂清洗DEGREASING, EMULSION, DIPHASE 脱脂、乳化、固液相分离.♌ALKALINE CLEANING 碱洗SPRAY, SOAK, ELECTRO, ULTRASONIC 喷射、浸泡、电解、超声波♌ACID CLEANING 酸洗SOAK, ELECTRO 浸泡、电解HOW CLEANERS WORK 清洗剂如何工作♌DISPERSION 分散♌SAPONIFICATION皂化♌EMULSIFICATION乳化DISPERSION分散DISPERSION IS A METHOD WHEREBY SOLID PARTICLES ARE BROKEN DOWN TO SMALL PARTICLES BY THE ACTION OF SURFACTANTS AND OTHER COMPONENTS IN A CLEANER. THE PRINCIPLE IS EFFECTIVE FOR RESIDUE LEFT FROM POLISHING OPERATIONS分散是一种方法，固体的微粒通过表面活化剂和清洗剂中其它组分的作用分散成小的微粒。