Effects of Process Variables on the Structure and Properties of Hot Rolled 718 Bar

Autor: R.S. Minisandram, J.M. Moyer, L.A. Jackman, T.W. Miles
Rok vydání: 2001
Předmět:
Zdroj: Superalloys 718, 625, 706 and Various Derivatives (2001).
DOI: 10.7449/2001/superalloys_2001_259_268
Popis: An experiment was statistically designed to determine the effects of ten variables on the niicrostructure and mechanical properties of alloy 71 8 bar produced on Allvac's state-of-the-art, continuous, 10-stand rolling mill. A series of 32 rolling trials was conducted in which each \,xiable was set at one of two levels. Microstructures and mechanical properties lvere deteimined on samples taken after the material exited selected stands. Surface temperat~lres of the moving metal urere measured with pyronleters at six locations along the rolling mill. The grain size and mechanical properties after stand 4 are determined largely by the initial billet temperature. As rolling progresses, the speed of the finishing portion of the mill becomes increasingly important until it finally becomes the dominant factor. Correlations exist betm een surface temperature, n~icrostructure, and mechanical properties; these include the influence of delta phase distribution on stress-rupture properties. Experimental results agree m ell mith predictions of both surface and internal temperatures made ~vith a steady state, finite element model. The model is now available for optimizing rolling procedures. Superallo!,~ 7 IS. 625. 706 and Various Derivatives Editccl h!. E.A. Loria Th'lS (Thc hlinerals. hlztals 01c Materials Society). 2001
Databáze: OpenAIRE