Publicaties

Stress and residual stress are two crucial factors which play important roles in mechanical performance of materials, including fatigue and creep, hence measuring them is highly in demand. Pulse eddy current (PEC) and ultrasonic testing (UT) are two non-destructive tests (NDT) which are nominated to measure stresses and residual stresses by numerous scholars. However, both techniques suffer from lack of accuracy and reliability. One technique to ...

Ferrous shape memory alloys (SMAs) do not possess a complete shape recovery. Several attempts to improve the shape recovery still fail to achieve 100% recovery. For some applications, however, the recovery stress under constraint might be more important. In this work, a procedure was designed to measure these stresses under constraint in a Fe29MnSiCr SMA.The net recovery stress was defined as the maximal difference between the stresses developed ...

The use of modified couple stress theory to simulate the size-dependent phenomenon of composite laminate microplate is commonly limited to simple boundary conditions and mechanical bending load. The small-scale effects on bending and buckling on composite laminate microplate under complex boundary conditions in thermal environment have not been understood fully in the literature. Hence, this research develops, for the first time, a model to ...

Weld strength mismatch is a key factor with respect to the assessment of a flawed girth weld. However, it is challenging to assign a single strength mismatch value to girth welds, which are generally heterogeneous in terms of constitutive behavior. The authors have recently developed a method ('homogenization') to account for weld strength property variations in the estimation of crack driving force response and the corresponding tensile limit ...

A modelling technique for Large-Eddy Simulation is presented, in which the residual-stress tensor is reconstructed by applying an optimal convolution operator to the resolved stresses. This convolution operator is defined as a Taylor-series expansion in which the coefficients are determined using a dynamic procedure. The method is evaluated for the 1D Burger’s equation as proof of concept. Promising results are obtained.

One of the major challenges in the design of Bileaflet Mechanical Heart Valves (BMHVs) is reduction of the blood damage generated by non-physiological blood flow. Numerical simulations provide relevant insights into the (fluid) dynamics of the BMHV and are used for design optimisation. In this paper, a strong coupling algorithm for the partitioned Fluid-Structure Interaction (FSI) simulation of a BMHV is presented. The convergence of the ...

Fatigue crack growth behaviour in pipes fundamentally differs from fatigue growth in shafts and flat plates. The aim of this paper is to give a better understanding of this phenomenon. In a first part of the paper, the general principles of the fracture mechanics are concisely described. The energy approach as well as the stress intensity factor (SIF) approach are explained. An analytical method, a numeric method as well as an experimental ...

The EMC-signature of devices containing microcontrollers can differ due to thermal or mechanical stress. Research is presented to prove the feature selective validation method (FSV) to be sensitive enough to analyze differences in signatures.

A high amount of deformation below the non-recrystallization temperature (T-nr) is a common industrial practice to achieve a good combination of toughness and strength in microalloyed steels. To combine the industrially relevant optimum combination of high productivity and product quality, an accurate knowledge of T-nr and the recrystallization kinetics is required. Although a lot of literature data is available on the recrystallization ...