Author: W. F. SavagePublisher:
ISBN:
Category :
Languages : en
Pages : 104
Book Description
Prevention of Hydrogen-induced Cracking in HY-130 Weldments
Author: W. F. SavageThe Prevention of Hydrogen-Induced Cracking in HY-130 Weldments
Author: RENSSELAER POLYTECHNIC INST TROY N Y.Publisher:
ISBN:
Category :
Languages : en
Pages : 16
Book Description
The present research has the following objectives: (1) To evaluate the interrelationship among the mechanical, metallurgical, and chemical factors responsible for hydrogen-induced cracking in HY-130 steel weldments using the Augmented Strain Cracking Test. (2) To determine the effect of preheat and interpass temperatures and times on level of hydrogen retained. (3) To study, with the aid of acoustic emission technology and both electron and optical microscopy, the mechanisms for nucleation and propagation of hydrogen-induced cracks. (4) To recommend soundly based yet practical procedures for eliminating hydrogen-induced cracking in HY-130 weldments. Testing performed to date has been restricted to a constant augmented strain of 0.5%. This level of strain produces a stress in the outer fibers slightly in excess of the yield stress. Effects of the following are discussed: Hydrogen Content; Preheat; Postheat; Hydrogen Distribution Experiments.
Hydrogenassisted Cracking in HY-130 Weldments
Author: W. F. SavagePublisher:
ISBN:
Category :
Languages : en
Pages : 61
Book Description
The relative susceptibility to hydrogen-assisted cracking of AX-140 welds on HY-130 plate material and on AX-140 all-weld-metal specimens was investigated. Controlled amounts of diffusible hydrogen were introduced into these weldments by using the pulsed-current gas metal arc welding process with additions of hydrogen or moisture to the shielding gas. The critical hydrogen content required for crack initiation and propagation was determined by the augmented strain cracking (ASC) test. Crack initiation and propagation were monitored with acoustic-emission techniques. Although hydrogen-assisted cracking invariably initiated in the fusion zone, it frequently propagated into the heat-affected zone. Crack propagation through the weld metal was not always related to the solidification structure. The critical hydrogen content to initiate cracking in AX-140 welds on HY-130 plate was approximately 1 ppm, whereas in AX-140 welds on AX-140 all-weld-metal the critical hydrogen content was approximately 3 ppm. This difference is cracking susceptibility was ascribed to the difference between the base-metal and the fusion-zone analyses.
Use of Implant Testing to Evaluate the Susceptibility of HY-130 Steel Weldments to Hydrogen Embrittlement
Author: Bradley J. MasonPublisher:
ISBN:
Category : Mechanical engineering
Languages : en
Pages : 108
Book Description
The cracking that may occur near the fusion zone of a steel weldment can often be attributed to the embrittlement of the microstructure by hydrogen induced during the welding process. The modified implant test was used in this case to evaluate the hydrogen-assisted cracking susceptibility of three separate heats of HY-130 steel, which included both cast and wrought plate. Welding was accomplished by the gas metal-arc spray transfer process. Cracking in all plates was observed to initiate and propagate in an area near the weld interface. The exact location of the fractures varied according to the amounts of diffusible hydrogen present and the type of material being tested. The effect of stress intensity together with hydrogen content on the mode of fracture present is also addressed in detail. (Author).
Hydrogen-induced Cracking in HY-130 Steel
Author: Alan J. SilviaCorrosion of Weldments
Author: Joseph R. DavisPublisher: ASM International
ISBN: 1615030514
Category : Technology & Engineering
Languages : en
Pages : 228
Book Description
Corrosion failures of industrial components are commonly associated with welding. The reasons are many and varied. For example, welding may reduce the resistance to corrosion and environmentally assisted cracking by altering composition and microstructure, modifying mechanical properties, introducing residual stress, and creating physical defects. This book details the many forms of weld corrosion and the methods used to minimize weld corrosion. Chapters on specific alloys groups--carbon and alloy steels, stainless steels, high-nickel alloys, and nonferrous alloys--describe both general welding characteristics and the metallurgical factors that influence corrosion behavior. Corrosion problems associated with dissimilar metal weldments are also examined. Case histories document corrosion problems unique to specific industries including oil and gas, chemical processing, pulp and paper, and electric power. Special challenges caused by high-temperature environments are discussed. Commonly used methods to monitor weld corrosion and test methods for evaluation of intergranular, pitting, crevice, stress-corrosion cracking, and other forms of corrosion are also reviewed.
Scientific and Technical Aerospace Reports
Author: Hydrogen in HY-130 Weld Metal
Author: Michael D. HayesPublisher:
ISBN:
Category :
Languages : en
Pages : 55
Book Description
This is the final report on a program designed to evaluate the potential for using rare-earth materials to getter hydrogen during welding. The end objective was to reduce the potential for hydrogen embrittlement in HY-130 steel welds. This report briefly summarizes work conducted during the first three years of the program, during which time several varieties of rare-earth containing-electrodes were produced. Cracking problems during drawing were encountered when rare-earth materials were added to high-strength filler wires. A method of addition was found wherein rare-earth silicon and rare-earth nickel compounds were incorporated into a rare-earth cored wire. This wire was then used as a cold-wire addition and weldments were produced by the gas metal-arc process. However, impact properties of these welds were below specified limits. This was partially attributed to the poor welding performance resulting from the rare-earth additions. Increased arc instability resulted in spatter, bead irregularity, and poor wetting action. Weldability improved when argon-O2 mixtures were used but the oxygen addition to the shielding gas oxidized all of the rare earths.
Author: Emmett I. Husa
Author: