An Efficient Methodology towards Mechanical Characterization and Modelling of 18Ni300 AMed Steel in Extreme Loading and Temperature Conditions for Metal Cutting Applications

Abstract

A thorough control of the machining operations is essential to ensure the successful post-processing of additively manufactured components, which can be assessed through machinability tests endowed with numerical simulation of the metal cutting process. However, to accurately depict the complex metal cutting mechanism, it is not only necessary to develop robust numerical models but also to properly characterize the material behavior, which can be a long-winded process, especially for state-of-stress sensitive materials. In this paper, an efficient mechanical characterization methodology has been developed through the usage of both direct and inverse calibration procedures. Apart from the typical axisymmetric specimens (such as those used in compression and tensile tests), plane strain specimens have been applied in the constitutive law calibration accounting for plastic and damage behaviors. Orthogonal cutting experiments allowed the validation of the implemented numerical model for simulation of the metal cutting processes. Moreover, the numerical simulation of an industrial machining operation (longitudinal cylindrical turning) revealed a very reasonably prediction of cutting forces and chip morphology, which is crucial for the identification of favorable cutting scenarios for difficult-to-cut materials.

Microstructure Evolution Mechanism of AISI 1045 Steel Under High Speed Deformation

“…when metallic materials are subjected to extreme deformation loads characterized by high deformation speed and large strain, they usually undergo macroscopic localization of the deformation, form a concentrated shear zone, and result in plastic instability [1][2][3]. in earlier research on metal material microstructures, the bright white high-hardness bands in the concentrated deformation zone assumed to be martensitic products formed via phase transformation [4][5][6]. Later on, transmission electron microscopy, field emission scanning electron microscopy, and electron back-scattered diffraction (eBSD) were applied to investigate the microstructure, and the results proved that equiaxed non-distortion crystal grains of sub-micron size were formed in the concentrated deformation zone [7,8].…”

Impulse-Based Manufacturing Technologies

“…Therefore, technology-adapted material characterization and modelling is highly relevant in impulse-based manufacturing. Silva et al suggest a me-thodology for the mechanical characterization and modelling of materials under extreme load conditions considering strain, strain rate, temperature, and state of stress [12]. Al-though the validation in this paper is based on metal cutting, these load conditions show comprehensive similarities with the situation in impulse-based manufacturing, so the approach is relevant and could benefit these technologies, too.…”