A Method for Comparing the Fatigue Performance of Forged AZ80 Magnesium

A closed die forging process was developed to successfully forge an automotive suspension component from AZ80 Mg at a variety of different forging temperatures (300 °C, 450 °C). The properties of the forged component were compared and contrasted with other research works on forged AZ80 Mg at both an intermediate forging and full-scale component forging level. The monotonic response, as well as the stress and strain-controlled fatigue behaviours, were characterized for the forged materials. Stress, strain and energy-based fatigue data were used as a basis for comparison of the durability performance. The effects of the starting material, forging temperature, forging geometry/configuration were all studied and aided in developing a deeper understanding of the process-structure-properties relationship. In general, there is a larger improvement in the material properties due to forging with cast base material as the microstructural modification which enhances both the strength and ductility is more pronounced. In general, the optimum fatigue properties were achieved by using extruded base-material and forging using a closed-die process at higher strain rates and lower temperatures. The merits and drawbacks of various fatigue damage parameters (FDP’s) were investigated for predicting the fatigue behaviour of die-forged AZ80 Mg components, of those investigated, strain energy density (SED) proved to be the most robust method of comparison.

Numerical evaluation of forging process designs of a hybrid co-extruded demonstrator consisting of steel and aluminium.

Multi-material solutions represent a promising approach for the production of load-optimised parts. The combination of material-specific advantages of different materials in a single component allows the fulfilment of conflicting requirements e.g. high performance and low weight. Fabrication of hybrid components is challenging due to the dissimilar properties of the individual materials and requires the development of suitable manufacturing technologies. The present paper deals with the simulation-based design of a forming process for the production of a suspension control arm consisting of steel and aluminium. With the focus on material flow, two forming concepts, open-die and closed-die forging, were investigated, in order to ensure the required material distribution similar to the final part. In addition, a tool analysis was carried out to avoid thermo-mechanical overload of the tool system. It was found that the required material distribution can be achieved with both forming concepts. However, a closed-die forging concept is not suitable because of the high stresses in the forging dies exceed the tool steel’s strength.

Preform design in axial hot closed die forging by isothermal surface method. Part 3. Preform design of industrial cases

The isothermal surfaces method for preform design is proposed. The procedure for determining of the preform shape is given. The features in using of the method for forgings with various shapes are considered. The method is illustrated by industrial examples. The design algorithm uses the QForm metal forming simulation software to build isothermal surfaces and check the quality of the designed die geometry by finite element modeling, as well as specially developed version of the QFormDirect CAD based on SpaceClaimтм.

Preform design in axial hot closed die forging by isothermal surface method. Part 1. Overview of preform design methods. Theoretical aspects and algorithm of preform shape design

Methods of preform design in hot-die forging are analyzed. It is noted that despite numerous works in this fi eld, preform design is still often based on the trial-and-error method. The isothermal surfaces method for preform design is proposed and its mathematical basis is considered. The procedure for determining of the preform shape is given. The design algorithm uses the QForm metal forming simulation software to build isothermal surfaces and check in the quality of the designed die geometry by finite element modeling, as well as specially developed version of the QFormDirect CAD based on SpaceClaim™.

Preform design in axial hot closed die forging by isothermal surface method. Part 2. Application of isothermal surfaces method for complex shape forgings

The isothermal surfaces method for preform design is proposed. The procedure for determining of the preform shape is given. The features in using of the method for forgings with various shapes are considered. The method is illustrated by industrial examples. The design algorithm uses the QForm metal forming simulation software to build isothermal surfaces and check the quality of the designed die geometry by finite element modeling, as well as specially developed version of the QFormDirect CAD based on SpaceClaimтм.