A Combination of Keyhole GTAW with a Trapezoidal Interlayer: A New Insight into Armour Steel Welding

被引：7

作者：

Fei, Zhenyu ^{[1
,2
]}

Pan, Zengxi ^{[1
,2
]}

Cuiuri, Dominic ^{[1
,2
]}

Li, Huijun ^{[1
,2
]}

Gazder, Azdiar A. ^{[3
]}

机构：

[1] Univ Wollongong, Sch Mech Mat Mechatron & Biomed Engn, Northfield Ave, Wollongong, NSW 2522, Australia

[2] Def Mat Technol Ctr, 24 Wakefield St, Hawthorn, Vic 3122, Australia

[3] Univ Wollongong, Electron Microscopy Ctr, Squires Way, Wollongong, NSW 2500, Australia

来源：

MATERIALS | 2019年 / 12卷 / 21期

关键词：

K-GTAW; armour steel; interlayer; microstructure; low temperature phase transformation; keyhole welding; TRIP; BALLISTIC PERFORMANCE; DISLOCATION DENSITY; K-TIG; STRENGTH; MICROSTRUCTURES; TEMPERATURE; TOUGHNESS; MARTENSITE; MECHANISMS; FRACTURE;

D O I：

10.3390/ma12213571

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The ballistic performance of armour steel welds using austenitic filler materials is poor on account of the disparity in the mechanical properties of the weld and base metals. Consequently, a novel Keyhole Gas Tungsten Arc Welding process with a trapezoidal AISI309 austenitic stainless steel interlayer was developed to tailor chemical composition and microstructure by controlling the solidification sequence. Results show that the dilution rate in the weld metal region can reach up to 43.5% by placing a specially designed interlayer in between the base metal, providing a major scope for microstructure modification. Detailed weld analysis was undertaken by X-ray diffraction, optical and secondary and transmission electron microscopy, energy dispersive spectroscopy and electron back-scattering diffraction. The results from Vickers hardness indents and Charpy impact toughness testing at -40 degrees C show that the properties of the weld metal region are comparable to that of the base metal. This is ascribed to the weld metal comprising a two phase microstructure of martensite and retained austenite, which contribute to improvements in strength and toughness, respectively. Furthermore, the tailored chemical composition, microstructure and low temperature phase transformation in the weld metal may reduce the tendency toward both solidification cracking and hydrogen assisted cold cracking.

引用

页数：18

共 34 条

[31] Effect of microstructural refinement on the toughness of low carbon martensitic steel [J].