A novel solid particle erosion resistant Ti/TiN multilayer coating with additional energy absorbing nano-porous metal layers: Validation by FEM analysis
Venkataramana Bonu, Sharad Kumar, P.N. Sooraj, Harish C. Barshilia
Abstract
Because of higher energy absorbing capacity of porous metals, these materials are used in car crash protection, armours, etc. However, to the best of our knowledge the porous metals are not used in solid particle erosion (SPE) resistant coatings. Nanotechnology allowed development of effective erosion resistant coatings by reducing the grain size of coatings to ≤ 10 nm. As a further development to it, here the porous metal layers, sandwiched between blocks of Ti/TiN multilayers to develop the next generation SPE resistant coatings. Two different ultra-thin Ti/TiN (bi-layer ~7.5 nm, 373 bilayers) multi-layered coatings (each ~9 μm) with dense (Ti/TIN-D) and porous (Ti/TIN-P) Ti layers (320 nm) were deposited on Ti6Al4V substrates using magnetron sputtering system. The erosion tests were conducted with respect to erodent speed (30 to 100 m/s), angle (30 to 90°), and temperature (25 to 700 °C). The average erosion resistance performance of Ti/TIN-P coating is 44 times better than Ti6Al4V substrate and 3.3 times better than Ti/TIN-D coating for 100 m/s erodent speed. Finite element simulations were used to understand the superior performance of Ti/TIN-P over Ti/TIN-D coating for different speeds (20 to 100 m/s). The simulation results are in agreement with the experimental results.