Research on Liquid Forming Process of Nickel Superalloys Thin Sheet Metals

Abstract

The paper presents the study of drawability of thin sheet metals made of a nickel superalloy Inconel type. The manufacturing process of axisymmetric cup -cone and a closed section profile in the form of a circular tube were designed and analyzed. In both cases, working fluid-oil was used in place of the rigid tools. The process of forming liquid is currently the only alternative method for obtaining complex shapes, coatings, and especially if we do it with high-strength materials. In the case of nickel superalloys the search for efficient methods to manufacture of the shaped shell is one of the most considerable problems in aircraft industry [1][2][3][4][5]. However, the automotive industries have the same problem with so-called advanced high-strength steels (AHSS). Due to this, both industrial problems have been examined and the emphasis have been put on the process of liquid forming (hydroforming). The study includes physical tests and the corresponding numerical simulations performed, using the software Eta/Dynaform 5.9. Numerical analysis of the qualitative and quantitative forecasting enables the formability of materials with complex and unusual characteristics of the mechanical properties and forming technology. It has been found that only the computer aided design based on physical and numerical modeling, makes efficient plastic processing possible using a method of hydroforming. Drawability evaluation based on the determination of the mechanical properties of complex characteristics is an indispensable element of this design in the best practice of industrial manufacturing products made of thin sheet metals.

Archives of Metallurgy and Materials

“…For a more favorable local strain distribution, work on this solution will continue to be modified and improved towards simultaneous pressing of two sigmoid tubes. c) quantitative analysis of local major strain distribution [4]…”

“…A modern AutoGrid local strain analyzer and a method of image analysis of the deformed parting grids with mesh parameter of 1 mm diameter have been used for quantitative evaluation of drawability of Inconel alloy sheets. More details of Inconel alloys sheet metals forming limit curves determination are presented in previous publications [4,9,11,12]. FLC of Inconel 718 was implemented into material model of numerical simulation in Eta / Dynaform 5.9 software [13].…”

“…1a) was selected. Initial results of drawability and simulation tests were collected in [4][5][6][7][8][9][10]. The AutoGrid system of allowed determining forming limit curve (FLC) of Inconel 718 alloy and implemented it to the material model in the FEM simulation of the modeled forming process.…”

“…Fig.3. The modeling results of the conical tube liquid forming using Eta/Dynaform software: a) tolls set and charge material, b) view element after forming with color scale of local strain -qualitative analysis, c) quantitative analysis of local major strain distribution[4] …”

Application of the Numerical Model to Design the Geometry of a Unit Tool in the Innovative RTH Hydroforming Technology

“…These features, combined with the use of advanced materials and new measurement methods such as [4], make hydroforming applicable in many industries, e.g., aerospace, automotive, agricultural machinery, and medical equipment [5][6][7][8][9][10].…”