Numerical simulation and optimization of fine-blanking process for copper alloy sheet

When the fine-blanking process is used, secondary grinding or processing can be omitted because the shear surface of fine-blanking parts can achieve almost zero fracture zone requirements. The primary objective of the fine-blanking process is to reduce the fracture zone depth and die roll zone width. This study used a 2.5-mm-thick central processing unit (CPU) thermal heat spreader as an example. Finite element analysis software was employed to simulate and optimize the main eight process parameters that affect the fracture zone depth and die roll zone width after fine-blanking: the V-ring shape angle, V-ring height of the blank holder, V-ring height of the cavity, V-ring position, blank holder force, counter punch force, die clearance, and blanking velocity. Simulation analysis was conducted using the L18 (21 × 37) Taguchi orthogonal array experimental combination. The simulation results of the fracture zone depth and die roll zone width were optimized and analyzed as quality objectives using Taguchi’s smaller-the-better design. The analysis results revealed that with fracture zone depth as the quality objective, 0.164 mm was the optimal value, and counter punch force made the largest contribution of 25.89%. In addition, with die roll zone width as the quality objective, the optimal value was 1.274 mm, and V-ring height of the cavity made the largest contribution of 29.45%. Subsequently, this study selected fracture zone depth and die roll zone width as multicriteria quality objectives and used the robust multicriteria optimal approach and Pareto-optimal solutions to perform multicriteria optimization analysis. The results met the industry’s fraction zone depth standard (below 12% of blank thickness) and achieved a smaller die roll zone width.

Foreign Language Effect on Dishonesty

The purpose of this paper is to investigate whether the use of foreign languages affects individuals’ dishonesty. We recruited native Chinese speakers who can speak English as a foreign language at universities in China, and they were randomly assigned to a native language (NL) or foreign language (FL) condition. Participants in each condition were required to finish the same tasks, in which they would benefit more from lying; the tasks were administered in either Chinese or English. We conducted one die-roll game in Study 1 and one cheap-talk sender-receiver game in Study 2. In both Study 1 and Study 2, we found that the proportion of lying was significantly lower in the FL condition than in the NL condition. Our results imply that the FL effect on dishonesty may be due to the cognitive load of communicating in a FL.

Collaborative Settings Increase Dishonesty

The present study examines whether collaborative situations make individuals more dishonest in face-to-face settings. It also considers how this dishonesty unfolds over time. To address these questions, we employed a sequential dyadic die-rolling task in which two participants in a pair sitting face-to-face received a payoff only if both reported the same outcome when each one rolled their die. In each trial, one participant (role A) rolled a die first and reported the outcome. Then, the second participant (role B) was informed of A’s reported number, rolled a die as well, and reported the outcome. If their reported outcomes were identical, both of them received a reward. We also included an individual condition in which an individual subject rolled a die twice and received a reward if he/she reported the same die-roll outcome. We found that B lied significantly more than participants in the individual condition, whereas A lied as much as participants in the individual condition. Furthermore, when collaborating, more and more participants (both A and B) became dishonest as the game progressed, whereas there was no such trend among participants in the individual condition. These findings provide evidence indicating that collaborative settings increase dishonesty and that this effect becomes more evident as the collaboration progress.

Experimental Investigation of Process Forces and Part Quality for Fine Blanking of Stainless Steel with Inductive Heating

Fine blanking is a highly productive process of industrial mass production with which high quality components in particular but not exclusively for the automotive industry are produced. The manufacturing process faces its limits at elevated tensile strengths of the materials to be processed. Consequently, high-strength steels can currently only be fine blanked to a limited extent. This can be overcome by lowering the flow stress of high-strength steels by means of inductive heating. A steel of high importance especially for industries with high hygiene standards such as medical and nutrition production is the stainless steel X5CrNi18-10 (1.4301). As a metastable austenitic steel which can initiate cutting impact on the press through martensitization, fine blanking of stainless steel is a challenge. X5CrNi18-10 is not a high-strength steel per se but becomes difficult to process due to the high hardness of the martensite phase, known as transformation-induced plasticity (TRIP) effect. Thus, in order to combine the possible advantages of the fine blanking process with inductive heating and the important properties of stainless steel, fine blanking of this steel was investigated with inductive heating prior to the fine blanking. The process forces and product quality properties such as die roll were investigated and found to be advantageous in comparison to non-heated fine blanking specimens of the same steel. The process forces and the die roll height decreased due to the heating.

Numerical Simulation and Optimization of Fine-Blanking Process for Copper Alloy Sheet

When the fine-blanking process is used, secondary grinding or processing can be omitted because the shear surface of fine-blanking parts can achieve almost zero fracture zone requirements. Fine-blanking has the advantages of high precision and high production efficiency. It was originally used on watch parts, but with increasingly refined technology, it has been widely applied in computers, consumer electronics, communication products, and vehicle parts. The primary objective of the fine-blanking process is to reduce the fracture zone depth and die roll zone width. This study used a 2.5mm thick central processing unit (CPU) thermal heat spreader as an example. Finite element analysis software was employed to simulate and optimize the main eight process parameters that affect the fracture zone depth and die roll zone width after fine-blanking: the V-ring shape angle, V-ring height of the blank holder, V-ring height of the cavity, V-ring position, blank holder force, counter punch force, die clearance, and blanking velocity. Simulation analysis was conducted using the L18 (21×37) Taguchi orthogonal array experimental combination. The simulation results of the fracture zone depth and die roll zone width were optimized and analyzed as quality objectives using Taguchi’s smaller-the-better design. The analysis results revealed that with fracture zone depth as the quality objective, 0.164 mm was the optimal value, and counter punch force made the largest contribution of 25.89%. In addition, with die roll zone width as the quality objective, the optimal value was 1.274 mm, and V-ring height of the cavity made the largest contribution of 29.45%. Subsequently, this study selected fracture zone depth and die roll zone width as multi-criteria quality objectives and used the robust multi-criteria optimal approach and Pareto-optimal solutions to perform multi-criteria optimization analysis. The results revealed the optimal fracture zone depth and die roll zone width were 0.239 mm and 1.288 mm, respectively. Finally, the experimental results verified that the fracture zone depth was 0.230 mm and die roll zone width was 1.205 mm. The findings met the industry’s fraction zone depth standard (below 12% of blank thickness) and achieved a smaller die roll zone width.

Cheaters, Liars, or Both? A New Classification of Dishonesty Profiles

Experimental studies of dishonesty usually rely on population-level analyses, which compare the distribution of claimed rewards in an unsupervised, self-administered lottery (e.g., tossing a coin) with the expected lottery statistics (e.g., 50/50 chance of winning). Here, we provide a paradigm that measures dishonesty at the individual level and identifies new dishonesty profiles with specific theoretical interpretations. We found that among dishonest participants, (a) some did not bother implementing the lottery at all, (b) some implemented but lied about the lottery outcome, and (c) some violated instructions by repeating the lottery multiple times until obtaining an outcome they felt was acceptable. These results held both in the lab and with online participants. In Experiment 1 ( N = 178), the lottery was a coin toss, which permitted only a binary honest/dishonest response; Experiment 2 ( N = 172) employed a six-sided-die roll, which permitted gradations in dishonesty. We replicated some previous results and also provide a new, richer classification of dishonest behavior.

Trust and trustworthiness after negative random shocks

We investigate experimentally the effect of a negative endowment shock in a trust game to assess whether different causes of inequality have different effects on trust and trustworthiness. In our trust game there may be inequality in favor of the second mover and this may (or may not) be the result of a negative random shock (i.e., the outcome of a die roll) that decreases the endowment of the first-mover. Our findings suggest that inequality leads to differences in behavior. First-movers send more of their endowment and second-movers return more when there is inequality. However, we do not find support for the hypothesis that the cause of the inequality matters. Behavior after the occurrence of a random shock is not significantly different from the behavior when the inequality exists from the outset. Our results highlight that we have to be cautious when interpreting the effects on trust and trustworthiness of negative random shocks that occur in the field (e.g., natural disasters). Our results suggest that these effects are largely driven by the inequality caused by the shock and not by any of the additional characteristics of the shock like saliency or uncertainty.