The Analysis of the Technologic Parameters Influence in Obtaining the Alloyed Sintered Steels by Two-Steps Sintering
Journal Title: RECENT - Year 2009, Vol 10, Issue 27
Abstract
In the paper there are presented the results of the experimental research for elaborating Mn, Mo, Cr, B and Graphite alloyed steels. There were elaborated mixings with 3% Mn and Fe, 1.5% Mo, 1% Cr and 0.5% B, which have experienced a 20, 40 and 60 hours mechanical alloy and produced nanocomposite mixings with powder grains of about 300nm. In this sense there were compactized samples at 600, 700, 800 MPa. The samples were heated in argon, at 1250 ºC, then in the same cycle the temperature were reduced at 1100 ºC, and kept 60 minutes. There were analyzed both the samples obtained by two-steps sintering and the samples obtained by classic sintering. The experimental results pointed out that the nanostructured steels obtained by two-steps sintering have an increasing of the density, structural homogeneity and mechanical properties (hardness, friction coefficient), comparing to the classical sintering. There is also presented the optimization of the technological process of elaborating the alloyed steels. In this purpose it is used the factorial experiment and is established that the polynomial model of degree 2 is optimal for estimating the output surface corresponding to the required experimental element. The results of the graphical data processing using the soft STATISTICA 8.0 proved interesting information concerning the variation of the mechanical characteristics of the alloyed steels.
Authors and Affiliations
Ionela BUCŞE, Ion CIUPITU, Adela IONESCU
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