Herewith some of our latest developments and success!
Recently stainless steel ball valves were SCN treated as the previous thermal spray coating showed premature delamination due to under-caoting corrosion. Since SCN is a diffusion process, no delamination is posssible and it also provides good corrosion resistance. The valves have been running for months and at last inspection "no wear" was evident.
|Zinc Flake coatings go under many properietary names such as Geomet, Magni, Delta, Dacromet, etc however our 213 provides the same excellent results with > 1000 hrs SS resistance to red rust. In hot humid coastal conditions the coating performs much better than Zinc plating. Recently a company has swapped over from .Zn plating to 213 on structural parts as these were prematurely failing due to corrosion. This replaced Cadmium plating and is giving better performance with no detrimental environmental effects.|
|Nitriding of stainless typically ruins the corrosion resistance due to the Nitrogen robbing the matrix of Cr to form chromium nitrides. This is even more detrimental for duplex stainless steels where the right ratio of austenite/ferrite is important to provide excellent corrosion resistance. Changing the ratio due to high temperatures will cause issues. Recently, SAF 2205 Duples SS used in seawater hydraulic systems on yachts was SCN treated to 1. provide a hard, gall resistant surface, 2. to maintain the corrosion resistance and 3. to not disturb the austenite/ferrite ratio. The parts have been running for some time now without problems.|
|The TDCC has been supplying coated bolts, nuts and washers for armoured vehicles. These items requires salt spray resistance in excess of 1000 hrs – which was easily achieved.|
|Ceric Ammonium Nitrate ((NH4)2Ce(NO3)6) or CAN is an inorganic compound and a specialized oxidising agent. It is highly corrosive though and even stainless steels suffer severe corrosion when in contact, We recently coated a vessel with a unique PTFE-based coating which proved to be highly resistant to the corrosive effect of CAN. Rather than using exotic materials to fabricate new equipment, a conventional stainless base material was used and coated at much lower cost but with exceptional corrosion resistance.|
|Replacement of Thermal Spray: A stainless steel rotor used in the food industry that was previously thermal sprayed on the seal surfaces was succesfully replaced with a borided version. The previous issues were 1. corrosion occurring under the thermal spray layer which lead to spalling and 2. the cost of applying the thermal spray. Boriding is one of the few process that can create a super hard layer on the surface of stainless. Furthermore, it is diffused into the surface there cannot delaminate.|
|Punching thin aluminium foil: we developed a special foil punch and die set as calculations showed that the clearances and tolerances required for conventional punching of 16 µm foil would be impossible to keep and even to make the make the parts to. The new system cuts multiple holes in the foil with no burr.|
|High performance punches for high strength steel: we supplied high strength, high hardness punches to an European company who punches thin, high strength spring steel. After the calculations were done, the only suitable steel was an Erasteel ASP powder metallurgy steel with a PVD coating. We also designed the dies for optimum clearance. So far the parts have outperformed all other parts and we're looking to further improve performance now.|
|Anti Weld Spatter coatings – welding of parts result in weld spatter landing on shields which eventually lead to excessive build up and replacement of shields. The TDCC applied a Teflon based anti-spatter coating for a continuous welding line and the weld spatter easily wipe off leaving an almost new parts. The anti-spatter coating involves a special makeup which is very effective in preventing the hot spatter sticking to the surface.|
NAAMS Global Standard Components for Assembly and Stamping
Erasteel High Speed and Powder Metallurgical Steels