Warm Incremental Forming of Magnesium Alloys Using Hot Fluid as Heating Media

Abstract

Industrial application of magnesium alloys is increasing in the last decade due to the very high mechanical strength to weight ratio they present. Typical applications are aeronautic parts but their use in the automotive industry is also growing. The bigger the reduction of the vehicle weight is, which can be obtain using these alloys, the bigger the energy saving will be in the near future. However, the formability of these alloys is poor and they are very difficult to be formed at room temperature. Several works have been presented by different authors on the positive influence the temperature increase has to form magnesium alloys. Normal process temperature is about 200-250°C. In this paper warm incremental forming of magnesium alloys is investigated. The work focuses in the formability limits of the alloys and the identification of the optimal process parameters. Aiming to obtain a homogeneous temperature in the forming areas, hot fluid is used as heating media. Experimental results for different temperatures are presented and final microstructures are related to the possible deformation mechanism.

Experimental Study on Warm Incremental Tube Forming of AA6063 Aluminum Tubes

“…They showed that the forming angle is increased in addition to the reduction of the forming force. Galdos et al [11] used hot fluid to achieve a uniform temperature distribution in incremental forming of magnesium sheets. Based on their results, the maximum formability of AZ31 alloy obtained by this heating method is 250°C.…”

Induction Heating Validation of Dieless Single-Point Incremental Forming of AHSS

“…Another heating method was presented that involved exerting hot oil to increase the sheet metal temperature as described in [5]. In other investigations, an electrical current was applied that passed through the tool to heat up the sheet, which was studied by [6] to form a titanium alloy TiAl 2 Mn 1.5 .…”

Hot single-point incremental forming assisted by induction heating

“…Additional works applied insulated cylindrical heating chambers [14] and hot fluids [15] with the aim of increasing the temperature in the forming zone.…”

“…At this temperature, only low strength and some types of nonferrous metals can be formed. Meanwhile, the investigated methods in [12][13][14][15] were used to heat the blank sheet up to only 250°C. At the same time, the formerly mentioned warm SPIF was restricted to form small and uncomplicated shapes.…”