Mould design optimisation by FEM

Production can be briefly defined as creating something new as a result of effort. There are many different production methods. With the industrial revolutions, the number of these methods has increased, and these methods have developed. Over time, heavy and laborious work that people had to do began to be done by machines. The casting method, which is one of the most common production methods in the world, is to pour the molten metal or its alloy into a mould cavity suitable for the shape of the desired product and remove it from the mould after it solidifies. In this study, firstly, the manufacturing method by casting was mentioned, and the difficulties of mould design in the casting method were explained. Secondly, the benefits of computer-aided simulation programs for casting are explained. As an example, a model was designed and different runners were added to this model. These models, which were prepared afterwards, were cast in a virtual environment with the FLOW-3D CAST program, which is a simulation program. Casting results and casting defects after these castings were compared and interpreted. The results show that it is important for the casting quality to keep the runner diameters as small as possible in runner designs. Two or three times more air voids are formed in the sand mould casting method compared to the permanent mould casting. Additionally, it was observed that the casting material had less shrinkage in the sand mould casting method. It is concluded that sand mould casting is disadvantageous in terms of the parameter of time.

Investigation on Stir Casting Fabrication Method Issues Analysis of Aluminium Metal Matrix Composites

Among the various types of manufacturing process methods for discontinuous metal matrix composite, stir casting is the best suitable manufacturing process to fabricate particulate reinforced metal matrix composite. Its benefit is its simplicity, durability, and adaptability. The main issue in this process is proper wetting of reinforcement in aluminium matrix material. Only proper wetting results in a homogeneous dispersion of reinforcement material, and these homogeneous dispersions help to improve the properties of metal matrix composite material. The purpose of this paper was to discuss the outline of the stir casting process, process parameters, and the contribution effect of process parameters. This paper also presents about of the conditions should follow during the addition of reinforcement material and matrix material pouring in mould cavity. This paper also discusses the conditions that must be met during the addition of reinforcement material and matrix material pouring in the mould cavity. This paper also looked into the impact and contribution of stirring casting time, speed, and temperature in aluminium metal matrix composites, as well as processing issues in aluminium metal matrix composites, challenges, and research opportunities.

Optimisation of Mould Design for Injection Moulding – Numerical Approach

Computer simulation of injection moulding process is a powerful tool for optimisation of moulded part geometry, mould design and processing parameters. One of the most frequent faults of the injection moulded parts is their warpage, which is a result of uneven cooling conditions in the mould cavity as well as after part ejection from the mould and cooling down to the environmental temperature. With computer simulation of the injection moulding process it is possible to predict potential areas of moulded part warpage and to apply the remedies to compensate/minimize the value of the moulded part warpage. The paper presents application of simulation software Moldex 3D in the process of optimising mould design for injection moulding of thermoplastic casing.

A Casting Mould for Rapid Tube Hydroforming Prototyping

In recent years, hydroforming has clearly expanded its range of industrial applications due to the growing interest in products which combine high strength with low weight. A current limitation of this technology was its economically justified production volume since the costs of producing tools eliminates the possibility of using hydroforming technology in prototype and single part production. The paper presents a freshly patented solution that allows for single part hydroforming. The new technology combines traditional hydroforming machines with a new approach to tool production. The new rapid die is made quickly and cheaply. The use of materials known from the production of foundry moulds causes the die to deform during hydroforming, but it is a controlled deformation. Thanks to the use of numerical modelling, the deformation of the mould cavity is predicted and taken into account at the design stage. The article presents important issues that need to be considered in the design of this innovative process.

Control of the Mg-Treated Iron Casting Skin Formation by S-Diffusion Blocking at the Metal–Mould Interface

Having established that sulphur presence in the mould materials appears to have an important contribution in graphite degeneration at least in the casting surface layer, a research program is undertaken to explore the possible beneficial effect of sulphur diffusion blocking at the metal–mould interface. Test samples, with and without a thin steel sheet (up to 3 mm thickness) application on the inner surface of the mould cavity, before iron melt pouring, are considered for structure analysis. A higher nodulizing potential (0.048% Mgres, 0.015% Ceres, and 0.006% Lares) decreases the occurrence of surface graphite degeneration in castings obtained in rigid chemically bonded resin sand moulds, using P-toluol sulfonic acid (PTSA) hardener (S-including), but it is not enough to avoid this phenomenon (200–400 μm skin in present experimental conditions). The casting skin appears to have different values, depending on the evaluation technique (un- and Nital-etching direct measurement, or graphite parameters variation on the casting section). In the presence of a thin steel sheet at the metal–mould interface, the casting skin thickness decreases or is just excluded. It is supposed that it acts as a barrier, blocking S-diffusion from the mould media into the iron melt. Without this S-diffusion, the graphite degeneration in the casting surface layer could be avoided, or at least diminished. For industrial application, the increasing of residual content of nodulizing elements is a limited solution, and it is recommended to use barriers to block S transfer on the mould/metal surface, such as dense coatings or coatings with desulphurization capacity.

Shaping Soft Robotic Microactuators by Wire Electrical Discharge Grinding

Inflatable soft microactuators typically consist of an elastic material with an internal void that can be inflated to generate a deformation. A crucial feature of these actuators is the shape of ther inflatable void as it determines the bending motion. Due to fabrication limitations, low complex void geometries are the de facto standard, severely restricting attainable motions. This paper introduces wire electrical discharge grinding (WEDG) for shaping the inflatable void, increasing their complexity. This approach enables the creation of new deformation patterns and functionalities. The WEDG process is used to create various moulds to cast rubber microactuators. These microactuators are fabricated through a bonding-free micromoulding process, which is highly sensitive to the accuracy of the mould. The mould cavity (outside of the actuator) is defined by micromilling, whereas the mould insert (inner cavity of the actuator) is defined by WEDG. The deformation patterns are evaluated with a multi-segment linear bending model. The produced microactuators are also characterised and compared with respect to the morphology of the inner cavity. All microactuators have a cylindrical shape with a length of 8 mm and a diameter of 0.8 mm. Actuation tests at a maximum pressure of 50 kPa indicate that complex deformation patterns such as curling, differential bending or multi-points bending can be achieved.

Polymer Based Injection Mould Cavity Inserts: An Influence on Crystallization and Thermo-Mechanical Properties of Injection Moulded Parts

Injection moulding is a major used technology in mass production of high-quality plastic and composite parts. Once the initial costs have been paid the price per produced part is extremely low and part is then created up to million times. On the other hand, the product development process is time-consuming and costly due to preparation time. Therefore, the efficiency and similarity to real production are essential. Injection moulding into polymer injection mould cavity inserts appears to be an appropriate step in the product development process in particular concerning quickly developing additive manufacturing technologies. Though polymers are thermal insulators, therefore, cooling time is longer compared to injection into fully metal moulds. The impact of different cooling conditions is a change in the crystallization of injected material causing different mechanical properties of products. Removable injection mould cavity inserts were made from PET (Polyethylene terephthalate), PEEK (Polyether ether ketone), PSU (Polysulfone) and PTFE (Polytetrafluoroethylene). The main goal was to compare crystallization and thermo‑mechanical properties of injected PP (Polypropylen) parts into polymer cavity inserts to those injected into a steel mould.