| The cold-rolled automobile sheet is one of the most important products of Baosteel, with the continuous improvement of production process of automobile sheet,the methods of quality inspection also has made progree.With the development and progress of science and technology and computer control technology, the test machine adopts automatic processing technology of electronic test and test data.In the use of electronic tensile testing machine, correctly set control modes and control parameters, to complete the test and obtain accurate test data is crucial.When the test standard, sample size and testing conditions are changed, the test results may be different.Through the typical case of several automotive steel plate detection, gives a detail explanation about how we solved them through some new software and tables and figs.And draws several conclusions below:(1)Through the study of the chemical compositions of IF steel, smelting, hot rolling and cold rolling production process, the final mechanical properties of IF steel and high strength IF steel for automobile.(2)We test three kinds of dimensions of tensile specimens for the plastic strain ratio (r value) of the cold rolled steel sheet. The analysis of test data shows that the plastic strain ratio (r value) will decrease if the gauge length of the test is close to the parallel length of the specimen. So caution should be exercised when the JIS No.5 specimen is used.(3)Here are some measure condition items which have influence on BH values of BH steel sheets during measure process, such as bake temperature, heating time and heating media, tensile speeds as well as different tensile machines. Quantitative influence for each condition items be reported in the paper.(4)According the request of Japanese custom,the Wca should be inspected.So we set a test condition of 25mm traversing length and Gaussian and Lf filter to do this test.Also,it’s clear that PPI is one of parameters in R-Profile,and it is related to the real length of the test. |
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