TY - JOUR

T1 - Influence of residual stresses in hard tool coatings on the cutting performance

AU - Bobzin, K.

AU - Brögelmann, T.

AU - Maier, H. J.

AU - Heidenblut, T.

AU - Kahra, C.

AU - Carlet, M.

N1 - Funding Information: The authors gratefully acknowledge financial support from the German Research Foundation (Deutsche Forschungsgemeinschaft ), within the project BO 1979/48-1 “Influence of HPPMS pulse parameters on stoichiometry and the formation of reaction layers on nitridic hard coatings for cutting” ( 321041164 ). Silvia Richter from the Central Facility for Electron Microscopy (GFE) of the RWTH Aachen University is acknowledged for measuring the chemical composition of the coatings by EPMA.

PY - 2021/9

Y1 - 2021/9

N2 - During the hard machining of powder metallurgical high-speed steel, finely dispersed carbides in the steel expose the tools to both thermal and mechanical load. This can influence the cutting performance and cause damage to the tools such as premature abrasive and adhesive wear. Thin hard coatings like TiAlN deposited by physical vapor deposition are widely used in order to improve the tool performance. High power pulsed magnetron sputtering (HPPMS) results in technical benefits, such as a more homogeneous coating thickness distribution on the tools compared to direct current magnetron sputtering (dcMS). The advantages of HPPMS can be combined with the high deposition rates of dcMS leading to a higher economic efficiency conducting a dcMS/HPPMS hybrid process. Adding silicon to the coating system TiAlCrN results in TiAlCrSiN leading to a nanocomposite coating architecture with improved mechanical properties. The influence of the residual stresses on the mechanical properties and on the roughing performance of nanocomposite coatings is of high interest and was therefore investigated in the present study. Four different TiAlCrSiN hybrid coatings deposited with four different substrate bias potentials were examined for this purpose. The residual stresses and the mechanical properties including the resistance against crack formation as well as the compound properties of the coatings on cemented carbide were investigated. Finally, the roughing performance of the coated cemented carbide tools were tested by milling the powder metallurgical high-speed steel HS6-5-3C. For the coatings investigated, it can be concluded that a compressive residual stress state of approx. -2 GPa ≤ σ ≤ −3 GPa leads to the highest resistance against crack formation, and thus to the best cutting performance.

AB - During the hard machining of powder metallurgical high-speed steel, finely dispersed carbides in the steel expose the tools to both thermal and mechanical load. This can influence the cutting performance and cause damage to the tools such as premature abrasive and adhesive wear. Thin hard coatings like TiAlN deposited by physical vapor deposition are widely used in order to improve the tool performance. High power pulsed magnetron sputtering (HPPMS) results in technical benefits, such as a more homogeneous coating thickness distribution on the tools compared to direct current magnetron sputtering (dcMS). The advantages of HPPMS can be combined with the high deposition rates of dcMS leading to a higher economic efficiency conducting a dcMS/HPPMS hybrid process. Adding silicon to the coating system TiAlCrN results in TiAlCrSiN leading to a nanocomposite coating architecture with improved mechanical properties. The influence of the residual stresses on the mechanical properties and on the roughing performance of nanocomposite coatings is of high interest and was therefore investigated in the present study. Four different TiAlCrSiN hybrid coatings deposited with four different substrate bias potentials were examined for this purpose. The residual stresses and the mechanical properties including the resistance against crack formation as well as the compound properties of the coatings on cemented carbide were investigated. Finally, the roughing performance of the coated cemented carbide tools were tested by milling the powder metallurgical high-speed steel HS6-5-3C. For the coatings investigated, it can be concluded that a compressive residual stress state of approx. -2 GPa ≤ σ ≤ −3 GPa leads to the highest resistance against crack formation, and thus to the best cutting performance.

KW - Cutting

KW - High speed steel

KW - Nanocomposite

KW - Residual stresses

KW - Substrate bias

KW - TiAlCrSiN

UR - http://www.scopus.com/inward/record.url?scp=85112467402&partnerID=8YFLogxK

U2 - 10.1016/j.jmapro.2021.08.011

DO - 10.1016/j.jmapro.2021.08.011

M3 - Article

AN - SCOPUS:85112467402

VL - 69

SP - 340

EP - 350

JO - Journal of manufacturing processes

JF - Journal of manufacturing processes

SN - 1526-6125

ER -