MP2S (Mineral Pickling Stainless Steel), an ISERCO subsidiary, now has two surface treatment lines using SUBLIMOTION-process® technology. This patented technology is designed for the treatment of stainless steel.
Why treat stainless steel equipment?
Stainless steel is a noble material, very appreciated in the industry and particularly in the food, chemical, or pharmaceutical sectors. This metal is known for its thermal resistance and its durability over time. It requires low maintenance and has an inert surface that prevents parasitic substances from modifying the properties of the product in contact with stainless steel.
However, although it is endowed with many qualities, stainless steel contains iron, and it is not totally infallible to oxidation. The ability of stainless steel to resist corrosion can be altered by a polluted and humid environment or by the presence of acids and important scratches on its surface. Therefore, it is necessary to give stainless steel surface treatment. This allows to protect it more, to reinforce its anti-corrosive capacity but also to eliminate impurities of the oxide type which can be formed during the welding.
How were the stainless steel parts treated at ISERCO?
Before the arrival of the SUBLIMOTION-process® at ISERCO, the stainless steel parts were immersed in several successive baths. They were chemically pickled, rinsed, passivated, and rinsed again. For aesthetic purposes, surface micro blasting was offered on the external parts of the devices.
The purpose of the acid is to pickle the stainless steel surface, making it completely homogeneous. This acid bath also protects the metal and destroys the heating marks caused during welding.
Immersion in a passivating bath serves to block the acid. Passivation allows the formation of a thin protective film of compact and homogeneous chromium oxide. This gives the stainless steel a higher resistance against corrosion. A passivating bath also decontaminates the surface. It eliminates the presence of oil and grease that may have adhered during the manufacturing process.
Finally, micro blasting gives a homogeneous aspect to the stainless steel while giving it a satin finish.
The process described above has a major flaw, the use of harmful chemicals. Moreover, it requires the reprocessing of the latter, thus generating a second source of pollution. Furthermore, to the obvious fact that chemicals are harmful to the environment, it was inconceivable not to opt for an innovative solution that has been approved for several years. These are the reasons that pushed ISERCO to create MP2S and to choose the SUBLIMOTION-process®.
This process requires only one treatment step which is more efficient, healthier, and more environmentally friendly.
What is the SUBLIMOTION-process®?
Originally, the SUBLIMOTION-process® is a surface cleaning and conditioning process developed by Phibo Industries. It is a treatment by a projection of an aqueous solution of water and an abrasive made of inert microparticles. It is a process that allows the cleaning of surfaces in an ecological, durable, and non-destructive way. Moreover, this process does not present any risk for the operator.
The SUBLIMOTION-process® treatment of stainless steel can generate a unique and very specific topography, in which all parameters are optimized to obtain a surface with minimal adhesion and ideal cleanability. As a result, the treated parts have surfaces that are less susceptible to the adhesion of residual materials during the production process. It also increases the corrosion and therefore fatigue resistance of stainless steel.
This solution has other benefits with easier cleaning, significantly reduced microbial retention, and a specific finish that is easily reproducible. It allows obtaining a surface with a homogeneous roughness and a satin-gloss finish. There is no risk of ferrous contamination. The SUBLIMOTION-process® finish is insensitive to temperature fluctuations. It is also an economic process developed from sustainable technology.
In which areas of application can this process be used?
This surface treatment for stainless steel parts is a particularly suitable solution for industries handling products where any risk of contamination must be excluded. This is the case in the food industry, an industry that is very much regulated by food and hygiene standards. It is a sector where hygiene is a factor of capital importance since it can impact the health of the consumer. Therefore, the production equipment is cleaned and disinfected regularly. The SUBLIMOTION-process® improves the hygienic properties and the cleanability of the treated surface. It also corrects defects on the stainless steel surface such as discolorations in the welding areas or micro cracks. It removes all traces of grease stains and other contaminants. Moreover, the absence of constituents or chemical products in the process of treatment of stainless steel by SUBLIMOTION allows a drastic reduction of the risks of food contamination.
The properties brought about by the surface treatment with SUBLIMOTION-process® are also perfectly suited for other sectors governed by hygiene standards. These include the pharmaceutical, chemical, and cosmetics industries.
Finally, the SUBLIMOTION-process® is mainly used for the treatment of stainless steel surfaces, but it can also be used for the cleaning of other materials such as titanium, aluminum, or brass.
This process can be adapted to many sectors and to all types of parts, offering incomparable results in terms of surface treatment.
Frequently asked questions
Is this treatment a treatment solution and/or a cleaning solution?
Basically, it is a surface pre-conditioning process. This makes the surfaces less susceptible to the adhesion of residual materials during the production process. However, the process can also be used for intermediate cleaning.
What are the consequences on parts with a polish (RA of 0.10 to 0.05)? Is this neutral, does it improve or degrade the polishing?
If we only consider the Ra value, it will increase slightly (around 0.20-0.25 µm). However, this change in Ra value is not necessarily a problem. A surface is a 3D topography that is also determined by many other parameters. Thus, surfaces with the same Ra can have completely different adhesion properties. Indeed, the other topography parameters (such as Rz, Rmax, Pc, Wf…) are different between these surfaces.
The SUBLIMOTION-process® creates a unique and very specific topography, in which all parameters are optimized to obtain a surface with minimal adhesion and optimal cleanability.
What is the duration of action after a production, especially in a high-temperature environment?
The SUBLIMOTION finish is insensitive to temperature fluctuations. The life of the treatment is linked to the external particles encountering the material, variable according to their abrasiveness.
Is there an interest compared to machining techniques (milling, electro-erosion …)?
The SUBLIMOTION-process® cleans and reconditions the machined surfaces to a pure surface, less susceptible to adhesion and easier to clean.
What results on an eroded surface?
This depends on the condition of the eroded surface. The SUBLIMOTION-process® works on a micro-scale, it cannot correct “errors” on a macro-scale.
Are the actions the same on all stainless steel, bronze, or aluminum?
Yes, the SUBLIMOTION-process® achieves the same properties and results on these materials.
Is it a surface treatment, or a substrate contribution?
It is a surface treatment.
Can the SUBLIMOTION-process® be a means of preparation before treatment (chrome plating type …)?
In terms of surface purification before treatment, yes, but we cannot forget that SUBLIMOTION-finishing is LESS sensitive to adhesion.
Is there a modification of the surface structure?
Absolutely, we change the structure on a microscopic scale.
Which factor is against the treatment? (Temperature / water / PVC chlorine, …)?
We preserve the physical and chemical properties of the base material (stainless steel, aluminum, etc.). In other words, the surface remains sensitive, for example, to mechanical wear due to harder materials (abrasions, etc.), which can scratch the surface and thus “wear” the topography.
What are the sectors of activity concerned by the SUBLIMOTION-process®?
In a general way, the fields concerned are in places with the materials used such as stainless steel, aluminum, bronze, or titanium.