What Does Corrosive Wear Mean?
Corrosive wear is material degradation wherein both wear and corrosion wear mechanisms are present. The effects of both wear and corrosion can result in intense damage or material losses. The effects can be more severe than when encountering either of these two mechanisms alone.
Typically, surface failure such as erosion and abrasion results from the dynamic interaction between two surfaces. It is the kind of damage resulting from the synergistic attack of both wear and corrosion when it takes place within a corrosive setting.
Having a clear understanding of the causes and nature of corrosive wear is important in choosing and using components or parts.
Corrosionpedia Explains Corrosive Wear
Corrosive wear is the result of acids and chemicals that are commonly produced in plastic processing, since these substances attack screws' and barrels' surfaces. The main characteristic of corrosive wear is pitting, which typically takes place in the last flights of the metering and transition zone. These pits could also lead to:
All of these may result in burned or blackened particles in various parts.
One of the major causes of corrosive wear is inappropriate component materials. For best practices, it is always recommended to make use of materials with excellent corrosion resistance properties. For instance, materials that work perfectly with screws and barrel linings include nickel alloys, hardened stainless steel as well as iron-free materials. Other factors that lead to corrosion wear include:
- Improper design
- Inappropriate heat profile
- Insufficient moisture removal
Avoiding corrosion wear can be accomplished by:
- Reducing temperature, speed and load
- Enhancing oil cooling
- Employing compatible materials
- Utilizing surface coatings like phosphate
- Ion implantation to modify surfaces
- Making use of highly viscous oil in order to break up surfaces
- Employing extreme pressure through additives like borate compounds