Cutting forces analysis in additive manufactured AISI H13 alloy

Title: Cutting forces analysis in additive manufactured AISI H13 alloy

Authors and full affiliations: Filippo Montevecchi, Niccolò Grossi, Hisataka Takagi, Antonio Scippa, Hiroyuki Sasahara, Gianni Campatelli

Keyword: Machinability; Milling; Cutting; Force

Abstract: Combining Additive Manufacturing (AM) and traditional machining processes is essential to meet components functional requirements. However significant differences arise in machining AM and wrought parts. Previous works highlighted the increasing of tool wear and worse surface finish. In this paper cutting forces are investigated as an indicator of material machinability. Milling cutting force coefficients are identified using mechanistic approach, comparing AISI-H13 wrought and AM specimen. Cutting force behaviour was investigated for two AM technologies: laser deposition (LENS) and wire-arc additive manufacturing (WAAM). Results show a general increase of cutting forces and coefficients of both AM materials, suggesting AM parts reduced machinability. Therefore, different cutting parameters should be selected for the AM material to achieve a sustainable production.

Purpose: The objective of this work is providing a comparison between cutting forces in milling AM and wrought AISI H13 steel.

Design/methodology/approach: The analysis was carried out for two different AM technologies: Laser-Engineered-Net-Shaping (LENS) and Wire-Arc-Additive-Manufacturing (WAAM). The analyzed material was AISI H13. Then Milling tests were carried out on wrought, LENS and WAAM specimens measuring the cutting forces with a table dynamometer. Measured cutting forces were used to compute cutting force coefficients as defined in Altintas et al. mechanistic cutting force model.

Findings: cutting force values are significantly higher in LENS and WAAM material.

Practical implications: this work highlights that AISI H13 AM material are harder to be machined, compared to the same material at wrought state. Indeed, results show a significant increase of cutting forces and cutting force coefficients. So a more powerful machine is needed, or a specific definition of cutting parameters for milling operation of AM parts.

Full reference: Procedia CIRP 46

Link: www.sciencedirect.com/science/article/pii/S2212827116301895