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Punch-stretch tests were conducted on Advanced High Strength Steel (AHSS) specimens. A special stretching mechanism with two embedded high resolution digital cameras had been designed and used in punch-stretch tests. The deforming processes were recorded by the cameras and the full-field strain distribution for each specimen was evaluated using Digital Image Correlation (DIC) technique, a full-field, non-contact, high accuracy optical and computational technique for contour, displacement and strain measurement. Data of Strain path, necking and other strain behavior were extracted using DIC. Different data analysis methods were tried to achieve useful information for predicting the failure. The data set could be used for researches on the effect of the strain path on the forming limit.

Advanced high strength steels (AHSS) are increasingly used in automotive industry. A major issue for AHSS stamping is edge cracking. This failure mode is difficult to predict by conventional forming limit curve (FLC). The material edge stretchability is mainly evaluated using the hole expansion test. In this study, digital Image Correlation (DIC) is applied for strain measurement. DIC is a non-contact, full field, high accuracy and direct measurement technique that provides more detailed information for the evolution of strains on the sheet surface. Tests were conducted for five AHSS and nine cases. This paper will explain in detail the DIC technique and its results.

The assembling accuracy of two contactors during the relay switch production is an important factor affecting the quality of relay. An embedded machine vision quality Inspection system has been developed for electric relay production line inspection. The proposed system can provide online feedback on the quality of the relays by measuring the distance of the gap between the contacts of them. Two CMOS imaging sensors are operated for image acquisition and the parallel working mode is realized under dual-channel mode. A red light illumination system has been adopted to eliminate the imaging noise from the reflection of the surfaces of copper sheet. Before the test, the features areas in the image of same type relay is selected as template and saved in the computer. During the inspection procedure, a rotation invariance detection scheme based on circular projection matching algorithm has been used for fast recognizing and locating detected object with the help of these feature areas.