Titanium anode (MMO)

Titanium anode (MMO) is produced by high-temperature sintering of titanium substrate coated with precious metal iridium salt. It is widely used in electroplating (deep-hole copper plating, electroplating, electroplating), electrolysis, and other hydrometallurgical industries.  The preparation and application of the electrode have been quite mature, with a history of 40 years. Compared with the traditional platinum-plated electrode in the alkaline copper process, the titanium anode has incomparable advantages over the platinum-plated electrode:  

1. Technical characteristics  

High current efficiency, excellent anti-corrosion performance;  Long service life of electrode;  Can follow the higher current density, operating current density: 10000A/M2 belongs to the industrial pure titanium as the base of oxygen evolution type anode. 

2, High catalytic activity  

It is well known that the platinum-plated electrode is a high oxygen potential (1.563V, relative to mercurous sulfate) electrode, while the MMO anode is a low oxygen evolution electrode (1.385V, relative to mercurous sulfate), which is more prone to oxygen evolution in the anodic oxygen evolution region.  Therefore, when electrolysis, the trough village is relatively low, more energy saving.  This phenomenon has been clearly reflected in the alkaline copper plating wall after copper foil treatment.  

3, Pollution-free Memos  

The anodic coating is a ceramic oxide of the precious metal iridium, which is a fairly stable oxide, almost insoluble in any acid and base, and the oxide coating is about 20-40µm, the overall amount of oxide coating is small.  As a result, MMO anodes do not contaminate the plating solution, much like platinum-plated electrodes.  

4, Cost-effective  

Having maintained the same service life as platinum-plated electrodes (coating thickness of 3.5mm), MMO anodes are about 80% of the price of platinum-plated electrodes. MMO electrodes have better electrochemical stability in alkaline copper plating electrolytes, as well as excellent electrolytic activity and durability.  Considering the cost of MMO anode and PT electrode, it is obvious that MMO electrode is economical.  

Since copper applications in printed circuits require a reverse pulse period (PPR), we know that the use of platinum-plated titanium insoluble anodes is prohibited.  However, this phenomenon can be avoided by using a stable size anode, and insoluble anode technology can successfully achieve performance advantages in such applications.  

6, The anode maintenance is the least.  There is no need to stop production to clean and replenish the anode, replace the anode bag, and re-coating the anode (productivity improvement, labor cost reduction);  

7, The life of the insoluble anode depends on the type, working current density and contact with various electroplating chemicals;  

Positive direction pulsation (PPR) plating anode  

Due to the rising price of metal materials, copper ions tend to concentrate on the edge of the hole (the high current density area) and deposit rapidly, while the central part of the hole (the low current density area) deposition rate is much slower.  This results in uneven distribution of copper deposition: the behavior is called "dog bone") at moderate current density operation will appear dog bone, at lower current density will appear barrel cracking phenomenon, at higher current density operation, will appear burning phenomenon.  For electroplated circuit board is undoubtedly a heavy impact.  

Reverse pulse electroplating anodes were also developed because the reaction of copper in printed circuit boards required the use of reverse pulse period (PPR) technology. Platinum-titanium insoluble anodes are known to be used in sulphuric acid electrolytes, where chloride is present in this current environment and after a period of time causes the platinum layer to peel off.  

Using positive and negative pulse electroplating anode has the following characteristics:  

1. The geometry of the anode remains the same, thus optimizing the current distribution.  

2, less maintenance of the anode.  There is no need to stop the production line to clean and replenish the anode. Replacing the anode bag improves productivity and reduces labor costs.  

3, to solve the problem of a uniform coating of deep hole electroplating: high current efficiency, can withstand 1000A/ M2 current density.  

4. It will not pollute the electroplating medium.  

The positive and negative pulse electroplating anode is an oxygen evolution type electrode with pure titanium (TA2) as the substrate.  Electric anode service life and excellent corrosion resistance.