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The Larson-Miller parameter is a means of predicting the lifetime of material vs. time and temperature using a correlative approach based on the Arrhenius rate equation. The value of the parameter is usually expressed as ''LMP''=''T''(''C'' + log ''t'') where ''C'' is a material specific constant often approximated as 20, ''t'' is the time in hours and ''T'' is the temperature in Kelvin. Creep-stress rupture data for high-temperature creep-resistant alloys are often plotted as log stress to rupture versus a combination of log time to rupture and temperature. One of the most common time–temperature parameters used to present this kind of data is the Larson-Miller (L.M.) parameter, which in generalized form is ''T'' = temperature, K or °R = stress-rupture time, h ''C'' = constant usually of order 20 According to the L.M. parameter, at a given stress level the log time to stress rupture plus a constant of the order of 20 multiplied by the temperature in kelvins or degrees Rankine remains constant for a given material. ==References== * F.R. Larson & J. Miller, ''Transactions ASME'', Vol. 74, p 765-771, 1952. * G. E. Fuchs, High Temperature Alloys, ''Kirk-Othmer Encyclopedia of Chemical Technology'' * Smith & Hashemi, ''Foundations of Material Science and Engineering'' * G.E. Dieter, ''Mechanical Metallurgy, Third Edition'', McGraw-Hill Inc., 1986, p 461-465, ISBN 0-07-016893-8. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Larson-Miller Parameter」の詳細全文を読む スポンサード リンク
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