Daily Illini November 5, 1911
"Seventeen railroad rails break every day," said Prof. H. P. Moore of the department of theoretical and applied mechanics speaking on "How Metals Fail" at the Champaign Lions club yesterday afternoon at the Inman hotel.
"Four ways in which we have
failure of metal parts are as follows:
"First the chemical corrosion. This failure of a metal is the least dangerous. Some high grades of steel corrode a little and then build a strong film over the hole. Some of the cheaper types of steel are not able to create such a strong film.
"There are three ways of preventing corrosion. One is to remove the corroding agent. Sometimes as in the case of the water tarffic the corrosion may be remedied by adding certain impurities to the water of which it has been previously lacking. The second way of preventing corrosion is by covering every minute space with paint. The last method is to add chromium to the metal.
"Secondly, the lack of elastic strength has much to do with the failure of metals. While a heavy load is on a beam it will bend. When the load is removed it should come back to its original place. If it does not the beam will finally lose its shape and become distorted. Eventually, if the imperfection is not remedied, the structure will collapse.
"The third cause of the failure of metals is 'creep.' Metals that are subjected to extremely high temperature slowly become distorted. As the distortion increases the structure will become useless. Chromium is being used to remedy 'creep'.
"The fourth way is known as the 'fatigue of metal.' This is the actual fracture Of metal parts or the failure of a metal that has been caused by a repeated load.
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