A new die design has been proposed for processing of materials using Equal Channel Angular Extrusion (ECAE). The proposed design is an improvement over the existing ones and has an additional attribute to process materials at high temperatures (up to 500 o C). The design has been tested for different materials at different temperatures and it has shown the benefit of reducing the load requirement during pressing. This benefit is attributed to the reduction of friction and appropriate tooling.
The fiber injection molding process is an innovative approach for the manufacturing of long fiber nonwoven preforms with little to no waste. An important property for the mechanical characteristics of the composite parts is the fiber orientation of the fiber injection molded nonwovens. In this paper a newly developed assemble method based on Fast Fourier Transform and improved Structure Tensor methods for the computation of the fiber orientation distribution in the local orientation by image analysis of transmitted light images is presented. For the computation of the fiber orientation, the Fast Fourier Transform and Structure Tensor methods are used. The new method is evaluated using simulated images and transmitted light images of real nonwovens to evaluate their accuracy. The computed fiber orientation distributions are compared to reference distributions by means of the Kullback–Leibler divergence. It is shown that the assemble method can perform accurate and reliable measurement of fiber orientation measurement and the modified Structure Tensor method improves results significantly compared to the current state of the art.
The use of shape memory alloys for micro-actuators constitutes a field of application in which copperaluminum-based alloys find their usefulness because they can reach higher activation temperatures and are easier to produce than titanium-based alloys, particularly by the method proposed in this work. SMA tapes are a two-dimensional structure that offers many design options such as stamping, punching, and deep drawing, but they are also suitable for laser cutting, engraving, stamping, and EDM machining. This work has been made to study the manufacture of copper-based shape memory alloys (SMAs) using the cold co-rolling process also called the cold-roll bonding (CRB) process. In this process, a thin metal sandwich can be produced with a rolling machine. This sandwich consists of layers of CuNiBe master alloy and Al. During the rolling phase, the sandwich has no shape memory effect (SME) or superelastic effect (SE), so thin strips can be easily produced. After the rolling phase, the sandwich is subjected to a complex heat treatment to gain the SME. To validate this process to produce Cu-based SMAs, several alloys with different CuAlNiBe compositions have been tested. The SMAs obtained were characterized by optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The martensitic transformation was studied by Differential Scanning Calorimetry (DSC) and SME and SE were studied by three-point bending tests. This work shows that the CRB is a good process for making a wide variety of Cu-based SMA ribbons.
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