Ejection Performance of Coated Core Pins Intended for Application on High Pressure Die Casting Tools for Aluminium Alloys Processing
Journal Title: Tribology in Industry - Year 2017, Vol 39, Issue 3
Abstract
In high pressure die casting (HPDC) process of aluminium alloys cast alloy soldering severely damages tool surfaces. It hampers casting ejection, reduces the casting quality and decreases the overall production efficiency. Thin ceramic PVD (physical vapor deposition) coatings applied on tool surfaces successfully reduce these effects. However, their performance is still not recognised for surfaces with various topographies. In this investigation, soldering tendency of Al-Si-Cu alloy toward EN X27CrMoV51 steel, plasma nitrided steel, CrN and TiAlN duplex PVD coatings is evaluated using ejection test. The coatings were prepared to a range of surface roughness and topographies. After the tests sample surfaces were analysed by different microscopy techniques and profilometry. It was found that the ejection performance is independent of the chemical composition of investigated materials. After the ejection, the cast alloy soldering layer was found on surfaces of all tested materials. This built-up layer formed by effects of mechanical soldering, without corrosion reactions. Coated samples displayed a pronounced dependence of ejection force on surface roughness and topography. By decreasing roughness, ejection force increased, which is a consequence of intensified adhesion effects. Presented findings are a novel information important for efficient application of PVD coatings intendent for protection of HPDC tools.
Authors and Affiliations
P. Terek, L. Kovačević, A. Miletić, D. Kukuruzović, B. Škorić
Carbide Type Influence on Tribological Properties of Hard Faced Steel Layer – Part I – Theoretical Considerations
This paper gives a theoretical review of influence of the most important alloying elements on steel, and review of the most important carbide-forming elements and states the conditions which elements should fulfill in or...
Tribological Study of Biocompatible Hybrid Organic Molecules Film with Antibacterial Effect
Optical glass is widely used in bioengineering and various utilities such as public touchscreen displays and mobile devices. This work evaluates the features of anti‐bacterial and anti‐adhesion on Octadecyltrichlorosilan...
Fracture Toughness and Tribological Wear Behaviour of Micro Alloyed Pearlitic- Ferritic Ductile Cast Iron
Fracture toughness and wear behaviour of micro alloyed ductile iron were investigated. Hardness, fracture, fracture toughness and wear tests were carried out on the ductile irons samples (D1, D2, D3, D4 and D5), containi...
Friction and Wear in Timing Belt Drives
Timing belt tooth goes into contact with a drive pulley, stretched to the maximum, because of the previous tension. When the contact begins the peak of the belt tooth makes the contact with the outer surface of the pulle...
Shakedown Behavior in Multiple Normal Loading-Unloading of an Elastic-Plastic Spherical Stick Contact
The effect of strain hardening and hardening rule on shakedown behavior is studied in a multiple normal interaction process of an elastic plastic sphere against a rigid flat using finite element software ANSYS under full...