Open AccessSTRENGTH OF MINING AND BUILDING EQUIPMENT MATERIALS SUBJECTED TO GIGACYCLE LOADING
Author(s) -
Mindaugas Leonavičius,
Gediminas Petraitis,
Marijonas Šukšta,
V. Svalbonas
Publication year - 2006
Publication title -
journal of civil engineering and management
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.529
H-Index - 47
eISSN - 1822-3605
pISSN - 1392-3730
DOI - 10.3846/13923730.2006.9636385
Subject(s) - dross , materials science , grinding , metallurgy , crack closure , stress concentration , bending , fracture mechanics , fatigue limit , composite material , stress (linguistics) , stress intensity factor , structural engineering , engineering , linguistics , philosophy
High‐strength cast iron is used for manufacturing the supporting elements of minerals and cement clinker grinding machines. The dross layer remains inside large dimension castings after manufacturing. It has worse mechanical properties and resistance to fatigue crack formation and propagation. In this paper, the results of an experimental investigation of cyclic bending strength of semi‐natural specimens from cast iron with a dross layer of 10–11 mm thickness are presented. The mechanical properties and structures of the base and dross layers differed considerably. Before testing the methods of defectoscopy were applied to detect technology defects. The stress ratio was r = ‐0,62 and the stress alternating range varied from 70 to 280 MPa. To 1*108cycles, crack growth was insignificant. Further crack propagation was controlled. The 1st specimen was broken after 3*108 and the 2nd one after 2*108 cycles. The dependencies of crack propagation on cycle number and stress intensity factor range were estimated. The dross layer stops crack propagation, when crack front passes from dross to base metal.