Experimental and computational investigation on dynamic fracture toughness (J1d) behavior of multi-pass SMA armor steel weldments. (April 2020)

• Record Type: Journal Article
• Authors: Saxena, Ambuj; Kumaraswamy, A.; Dwivedi, Shashi Prakash; Srivastava, Ashish Kumar; Maurya, Nagendra Kumar
• Is Part Of: Theoretical and applied fracture mechanics. Volume 106(2020)
• Publication Date: 2020-04
• Subjects: Armor steel weldments -- Fractrography -- Dynamic fracture toughness -- EPFM approach -- FEA -- JC hardening and damage model; Fracture mechanics -- Periodicals; 620.1126
• DOI: 10.1016/j.tafmec.2020.102502
• Languages: English
• ISSNs: 0167-8442

Abstract

Highlights: Influence of armor steel weldments microstructure on J1d behavior. Evaluation and comparison of different techniques for finding crack initiation point. A comparison between compliance change rate method vs. elastic plastic fracture mechanics (EPFM) approach for evaluating J1d values of investigating materials. Evaluation of analytical JC hardening and damage model parameters for Armor steel by a constrained optimization procedure. Developed the Explicit FEA model to simulate the impact process and predict the damage behavior for Armor steel. Abstract: Dynamic fracture toughness ( J1d ) behavior of shield metal arc ( SMA ) welding of armor grade Armox 500 T steels prepared with low hydrogen ferritic steel ( LHF ) and austenitic stainless ( ASS ) steel consumables have been evaluated and compared. Three different techniques have been described and implemented to evaluate the dynamic fracture toughness ( J1d ) of investigated materials. Further, the results have been compared with Elastic plastic fracture mechanics (EPFM ) approach. An investigation has also been performed regarding the influence of microstructures (for LHF and ASS weldments fusion zone) effect on dynamic fracture toughness ( J1d ) and fracture characteristic. Finally, a constrained optimization procedure of minimizing the mean absolute percent error ( MAPE ) has been used to determining the Johnson Cook ( JC ) hardening and Damage model for Armox 500 T to simulate the impact and damage behavior. Results revealed that, Dynamic fracture toughness ( J1d ) of weldment-2 (prepared by ASS consumables and consisted duplex microstructure) is 20% and 10% more than weldments-1 (prepared by LHF consumables and consisted acicular ferrite structure) and counterpart base metal (Armox 500 T). The MAPE and standard deviation between FEA and experimental results are less than 10% with a good value of regression coefficient ( R ) which shown the excellent prediction capability of developed model.