Laser-assisted asymmetric incremental sheet forming of titanium sheet metal parts

Abstract

Asymmetric Incremental Sheet Forming (AISF) is a relatively new manufacturing process. In AISF, a CNC driven forming tool imposes a localized plastic deformation as it moves along the contour of the desired part. Thus, the final shape is obtained by a sequence of localized plastic deformations. AISF is suitable for small series production of sheet metal parts as needed in aeronautical and medical applications. Two main process limits restrict the range of application of AISF in these fields. These are the low geometrical accuracy of parts made from titanium alloys or high strength steels and, for titanium alloys, the limited formability at room temperature. In this paper a new concept for laser-assisted AISF is introduced including the required components. Furthermore, the CAX tools used for programming the NC path for the forming tool and the laser spot are illustrated. First experimental results show that the formability of the alloy Ti Grade 5 (TiAl6V4), which is usu ally used in aeronautic applications, can be increased

Development of novel tools for electricity-assisted incremental sheet forming of titanium alloy

“…The high working temperature may cause tool oxidation and tool wear [10,11] and this leads to lowered surface quality and scratches [5]. To reduce the tool temperature, tool oxidation and improve the sheet surface quality, three major approaches were employed in this work: 1) Employment of high temperature alloy: other than the steel, high temperature nickel alloy GH4169 was employed in the tool design and development.…”

“…Various methods of heat generation in ISF have been reported including by using hot air blowers [1], conduction with a forming chamber [2], radiation by a laser beam [3][4][5][6], friction through tool rotation [7][8][9] or Joule heat by DC current [10][11][12][13][14].These technologies greatly enhanced the ISF capabilities in fabrication of lightweight alloys.…”

“…The tool may be made of various materials e.g. tungsten carbide [3,4,[10][11][12], die steel [5,6], high speed steel [7,13], H13 hot work steel [8], air-hardened D2 [9] and BOHLER K100 tool steel [14]. In some cases, wear-resistant or frictionreduction coating may be applied to the tool tip [3][4][5][6].…”

Finite Element Analysis of hot Single Point Incremental forming of hip prostheses

“…In order to improve the forming behavior of Ti6Al4V sheets, deformation under elevated temperatures is needed. Therefore, multiple concepts for warm ISF processes were recently developed and introduced in the technical literature [9,10]. It was shown that, by using hot ISF process, the formability of lightweight alloys among them Ti-6Al-4V can be significantly improved [11,12,13,14].…”

The Development of Incremental Sheet Forming from Flexible Forming to Fully Integrated Production of Sheet Metal Parts

“…In order to form e.g. titanium or magnesium alloys with a low formability at room temperature, heat-assisted ISF variants were developed, such as laser-assisted ISF by Duflou et al (2007) and Göttmann et al (2011), or ISF with resistance heating, see e.g. Göttmann et al (2012).…”