Normal impact behaviour of C/SiC rigid‐felt titanium alloy three‐layered plate

Abstract

In this paper, impact damage behaviours of C/SiC rigid‐felt titanium alloy three‐layered plate under normal impact are investigated. First, low velocity impact experiment of the three‐layered plate is performed by means of a drop weight impact apparatus. Second, the finite element model of the three‐layered plate is established using a damage constitutive model; also, the influences of the initial kinetic energy (the initial velocity and the mass of the impactor) on stress distributions and damage patterns of the three‐layered plate are analysed. Finally, the energy dissipation mechanisms and failure characterizations of the three‐layered plate are discussed; also, the agreements of physical variables and damage morphologies between experimental and numerical results validate the reliability of numerical simulation. The results will play an important role in designing and evaluating advanced thermal protection structure.

Compression‐compression fatigue performance of aluminium matrix composite foams reinforced by carbon nanotubes

“…Compared with the dense metal materials, aluminium (Al) foams possess many attractive properties such as large strength to weight ratio, acoustic insulation, energy absorption, and heat dissipation, which satisfy the applications in the fields of aerospace, defence military, and railway transportation. [1][2][3] Generally, the Al foams are divided into closed-cell and open-cell Al foams based on different preparation methods, such as melt foaming or powder metallurgy for closed-cell ones and space holder, chemical vapour deposition (CVD), or investment casting for open-cell ones. Previous reports of our group [4][5][6] have proved that the space-holder method could take precise control of parameters including porosity, distribution, shape, and size of pores.…”

High‐temperature testing in a Charpy impact pendulum using in‐situ Joule heating of the specimen

“…In Nomenclature: a, = specimen height (y direction); A, = area in the cross section of the specimen (yz plane); A C1 , = eutectoid temperature; A C3 , = austenitizing temperature; b, = specimen width (z direction); C, = specific heat; D, = density; h, = surface conductance; I, = electric current; P, = perlite phase; s, = perimeter of the cross section of the specimen (yz plane); t, = time; T, = cross-section temperature; T c , = temperature at the control thermocouple; T e , = environmental temperature; T notch , = temperature at the notch cross section; α, = ferrite phase; δ, = skin depth; ϵ m , = strain at maximum force in a tension test at low strain rates; γ, = austenite phase; λ, = thermal conductivity; μ 0 , = free space permeability; μ r , = relative permeability; ρ, = electrical resistivity; ω, = angular frequency of the electric current addition to differences in specimen size and geometry of the notch (flaw size, shape, and acuity), these techniques strongly differ in the strain rate, and correspondingly, a variety of definitions of transition temperature have emerged. The wide range of testing techniques includes tensile tests, 2 Charpy V-notch impact testing, 3,4 Pellini drop-weight tests, 5,6 impact tensile test, 7 and fracture toughness testing using compact tension and single-edge notched bend specimens. 8,9 In recent years, small punch testing 10,11 was also included in the list.…”

“…In addition to differences in specimen size and geometry of the notch (flaw size, shape, and acuity), these techniques strongly differ in the strain rate, and correspondingly, a variety of definitions of transition temperature have emerged. The wide range of testing techniques includes tensile tests, Charpy V‐notch impact testing, Pellini drop‐weight tests, impact tensile test, and fracture toughness testing using compact tension and single‐edge notched bend specimens . In recent years, small punch testing was also included in the list.…”

Low‐cycle fatigue behaviour of ductile closed‐cell aluminium alloy foams

“…The cellular structure of low‐density foams results in lightweight materials with excellent stiffness‐to‐weight ratio, high ability to absorb impact energy, good shear and fracture strength, exceptional heat transfer ability, which recommends them for a wide range of applications, from packaging materials in the form of paper‐based honeycomb cardboard up to sport, automotive, marine and aerospace industries.…”