A Quick Cycle Time Sensitivity Analysis of Boron Steel Hot Stamping

Abstract

Several vehicle platforms involving the hot stamping of manufactured parts are launched every year. Mass production represents a key step in the manufacturing process of an actual hot stamping part. In this step, the cycle time (consisting of cooling time (t1) and handling time (t2) components) must be optimized. During t1, the stamping tool (punch and die) is closed, for cooling of the part. The t2 components (i.e., inlet transfer time, press forming time (closing and opening), and outlet transfer time) define the production output that ensures process performance. However, cost is the main driver in automotive applications. Here, a cycle-time calculation based on the design of experiments (DOE) is proposed for formulating cost-effective formulas. An iterative one-dimensional heat transfer model for each DOE step is set up to simulate 10 hot stamping cycles; the part temperature after quenching in cycle number 10 (where steady conditions are achieved) was selected as the process output variable to be controlled in the DOE. Several DOE variables were considered. The DOE results were employed for the proposal of a simplified formula, which helps in assessing the cycle time with its excellent trade-off between calculation cost and reliability. The formula was validated by laboratory tests.

Thin-Wall Machining of Light Alloys: A Review of Models and Industrial Approaches

“…Industrial approach have been focused on the following:Virtual twins development integrates CAM and simulation to predict the machining behavior, the future real position of the surface to cut, and improve the machining efficiency by selecting the proper cutting parameter, toolpath, or prediction [152]. Adaptive control, which is used in production to improve the part quality and to feed the database models, detects the process instabilities or deformation through signal analysis and changing on-line the machining parameters.Fixture systems design and new approaches try to include adaptive control on the workholding or the stiffening devices to increase the product efficiency, allowing to use more aggressive cutting parameters.…”

“…Virtual twins development integrates CAM and simulation to predict the machining behavior, the future real position of the surface to cut, and improve the machining efficiency by selecting the proper cutting parameter, toolpath, or prediction [152].…”

The Influence of Surface Preparation of the Steel during the Renovation of the Car Body on Its Corrosion Resistance

“…High-strength steels, aluminum and composites for more expensive vehicles are used for the construction of the car body [5,6]. Gestamp is one of the manufacturers of car body elements who conduct research in the field of steel in the construction of vehicle bodies and machine parts [7,8]. These tests include hot stamping of steel as well as the evaluation of this process for the corrosion resistance of the car body sheet.…”

Die Material Selection Criteria for Aluminum Hot Stamping

“…The cooling rate of this heat treatment determines the mechanical properties of the formed part and has become an issue of interest both in steel [5][6][7][8] and aluminum [9,10] hot stamping. A high thermal conductivity tool material combined with a properly designed internal cooling channel system allows the right stabilization of die temperature [11] for the high production demands of the automotive industry.…”