Recent advances in the development of aerospace materials

Titanium alloys present superior properties such as high strength-to-weight ratio and resistance to corrosion but, possess poor machinability. In this study, influence of material constitutive models and elastic–viscoplastic finite element formulation on serrated chip formation for modeling of machining Ti–6Al–4V titanium alloy is investigated. Temperature-dependent flow softening based modified material models are proposed where flow softening phenomenon, strain hardening and thermal softening effects and their interactions are coupled. Orthogonal cutting experiments have been conducted with uncoated carbide (WC/Co) and TiAlN coated carbide cutting tools. Temperature-dependent flow softening parameters are validated on a set of experimental data by using measured cutting forces and chip morphology. Finite Element simulations are validated with experimental results at two different rake angles, three different undeformed chip thickness values and two different cutting speeds. The results reveal that material flow stress and finite element formulation greatly affects not only chip formation mechanism but also forces and temperatures predicted. Chip formation process for adiabatic shearing in machining Ti–6Al–4V alloy is successfully simulated using finite element models without implementing damage models.

Modified material constitutive models for serrated chip formation simulations and experimental validation in machining of titanium alloy Ti–6Al–4V

This paper presents an overview of the recent advances in high performance cutting of aerospace alloys and composite currently used in aeroengine and aerostructure applications. Progress in cutting tool development and its effect on tool wear and surface integrity characteristics of difficult to machine materials such as nickel based alloys, titanium and composites is presented. Further, advances in cutting technologies are discussed, focusing on the role of hybrid machining processes and cooling strategies (MQL, high pressure coolant, cryogenic) on machining performance. Finally, industrial perspectives are provided in the context of machining specific components where future challenges are discussed.

High performance cutting of advanced aerospace alloys and composite materials

Titanium alloys are known as difficult-to-machine materials The problems of machining titanium are many folds which depend on types of titanium alloys This paper investigates the underlying mechanisms of basic challenges, such as variation of chip thickness, high heat stress, high pressure loads, springback, and residual stress based on the available literature These are responsible for higher tool wear and worse machined surface integrity In addition, many cutting tool materials are inapt for machining titanium alloys as those materials are chemically reactive to titanium alloys under machining conditions To address these problems, latest techniques such as application of high pressure coolant, cryogenic cooling, tap testing, thermally enhanced machining, hybrid machining, and use of high conductive cutting tool and tool holder have also been discussed and correlated It seems that all the solutions are not yet well accepted in the industrial domain; further advancement in those fields are required to reduce the machining cost of titanium alloys

Problems and solutions in machining of titanium alloys

Welding and Joining of NiTi Shape Memory Alloys: A Review

https://hal.archives-ouvertes.fr/hal-01002827/document

Machinability of titanium alloys (Ti6Al4V and Ti555.3)

Comparison of the machinabilities of Ti6Al4V and TIMETAL® 54M using uncoated WC–Co tools

Orthogonal cutting force measurements and single-point tool life tests were conducted in order to analyze the sensitivity to heat treatment on the machinability of three titanium alloys: Ti6Al4V, Ti-5Al-4V-0.6Mo-0.4Fe (TIMETAL® 54M), and Ti6246. The Ti6246 alloy showed the highest tool wear rates and the higher cutting forces in all the heat treatment conditions which could be related to its higher mechanical properties. TIMETAL® 54M alloy, a newly developed alloy with similar mechanical properties to the more commonly used Ti6Al4V, showed the lowest wear rates. Microstructural changes due to heat treatment have some influence in the machinability of the alloys. The β annealed samples of the Ti6Al4V and TIMETAL® 54M alloys, with a very coarse lamellar microstructure, showed considerably shorter tool life and higher cutting forces. The rest of the heat treatments showed no significant influence in the machining behavior of the analyzed alloys as they do not cause important microstructural changes.

Influence of Heat Treatment on the Machinability of Titanium Alloys

High bandwidth temperature measurement in interrupted cutting of difficult to machine materials

Cyber-physical systems (CPS) have been developed in many industrial sectors and application domains in which the quality requirements of data acquired are a common factor. Data quality in CPS can deteriorate because of several factors such as sensor faults and failures due to operating in harsh and uncertain environments. How can software engineering and artificial intelligence (AI) help manage and tame data quality issues in CPS? This is the question we aimed to investigate in the SEA4DQ workshop. Emerging trends in software engineering need to take data quality management seriously as CPS are increasingly datacentric in their approach to acquiring and processing data along the edge-fog-cloud continuum. This workshop provided researchers and practitioners a forum for exchanging ideas, experiences, understanding of the problems, visions for the future, and promising solutions to the problems in data quality in CPS. Examples of topics include software/hardware architectures and frameworks for data quality management in CPS; software engineering and AI to detect anomalies in CPS data or to repair erroneous CPS data. SEA4DQ 2021, which took place on August 24th, 2021 was a satellite event of the ACM Joint European Software Engineering Conference and Symposium on the Foundations of Software Engineering (ESEC / FSE) 2021. The workshop attracted 35 international participants and was exciting with a great keynote, six excellent presentations, and concluded on a high note with a panel discussion. SEA4DQ was motivated by the common research interests from the EU projects for Zero-Defects Manufacturing such as InterQ and Dat4.Zero.

M. Armendia

Papers

Machinability of titanium alloys (Ti6Al4V and Ti555.3)

Comparison of the machinabilities of Ti6Al4V and TIMETAL® 54M using uncoated WC–Co tools

Influence of Heat Treatment on the Machinability of Titanium Alloys

High bandwidth temperature measurement in interrupted cutting of difficult to machine materials

Software Engineering and AI for Data Quality in Cyber- Physical Systems - SEA4DQ'21 Workshop Report