Effect of martensite on cold cracking in 600mpa grade fluxcored. Assessment of welding crack resistance of steel nm400 consists of the surface crack rate, section crack. Weld performance evaluation jfe technoresearch corporation. The reheat cracking sensitivity was increased with increasing bismuth content in the weld metal. Technical report development of steel plate products for. Hydro gen cracking is also known as cold cracking or delayed crack.
As already mentioned, straight y groove tests are suitable to reveal susceptibility of the weld metal for cracking while the other one for haz cracking. Testing of cold crack susceptibility of weld and heataffected zone in the root pass weld. Ygroove cracking test on the welding crack resistance of. Jfetecs staff, with its abundant experience in diverse types of tests and experiments, provides solutions from drafting of experiment plans and preparation of test specimens to actual evaluation testing utilizing the testing machines. Cold cracking susceptibility of austenitic and martensitic. Y groove cracking test was conducted to study the welding crack resistance of nm400 steel. Since local stress is one of the most important factors for.
The test results show that no cracking was observed when the. Us4091147a welded steel products having low sensitivity. Understanding weld symbols the groove weld meyer tool. Hydrogen cracking of ferriticaustenitic stainless steel. Investigation of hydrogen assisted crack in welding by. Repair weldability at overlaybase metal interface of. Jis31582016method of y groove weld cracking test foreign standard. All three of these cracking phenomena have been observed in austenitic stainless steels and nibase. A chart method to determine necessary preheat temperature.
Relationship between carbon equivalent and critical preheat temperature y groove weld cracking test ref. The invention discloses a test weld gap clearance ensuring method in an oblique y groove weld cracking test method and a test plate, belonging to the technical field of welding. Since no single universally accepted test is available to characterise cold cracking, the panel tentatively recom mended that a test procedure for y groove weld crackability test based on the japanese standard jis z 31581966 diagonal ytype weld crack testing methods shall be formulated. The y groove weld cracking test is widely used to investigate the necessary preheat temperature to avoid cold cracking. Evaluation of hydrogeninduced cracking in highstrength. Then, the mechanical characteristics of this specimen are clarified. Second, to improve their weldability, the proper preheating temperature was determined using y groove cracking test and mechanical property tests. The test weld shall be laid into the y groove as a single bead using an electrode of 4 mm diameter. Postheating includes postweld heat treatment pwht, immediate postweld heating ipwh, normalizing, quenching, and. Cold cracks in the weld metal were measured using the ygroove test, and four different preheating temperatures were employed from room. Numerical simulation of the effect of lowtemperature. Finally, a semiautomatic co 2 welding method was adopted, and a second mechanical property test was conducted to determine the proper welding wire. In order to obtain a high ferrite 85% level in y groove test runs, two panel assemblies were buttered with the high ferrite consumable prior to. High restraint conditions were tested using the y groove test.
Care shall be taken so that the start of the bead and the crater end do not occur in the slit region as illustrated in fig. Investigation of hydrogen assisted crack in welding by using y. Tekken y groove or lehigh ugroove test in order to obtain information about the cold cracking sensitivity during welding. This wire was made on an experimental basis to be applied to 980 mpa grade steel without preheating. Results of y groove weld cracking test on jfehiten 780le. If testing is required, a number of options are available. In order to confirm the weldability, y groove weld cracking tests were conducted in conformity to jis z 3158. Effect of preheating on welding cold crack sensitivity of. Welds were performed with ferritic, austenitic and duplex austenitic ferritic electrodes. Hot cracking tests an overview of present technologies. Using manual metal arc welding process and tekken test y grove test has been car ried out both. The welding was conducted at the condition of 260 a26 v23 cmmin with no preheating.
Nicr based highstrength weld metals have been developed to reduce preheating processes. The y groove weld cracking test is widely used to investigate the necessary preheat temperature to avoid cold cracking 38. In this study, the occurrence of cold cracking in high strength steel welds were investigated in terms of residual stress and hydrogen diffusion behavior. Weld performance evaluation for performance evaluation of welds joints, joint parts, leave it to jfetec. Defines the method of y groove weld cracking test for examining the likelihood of occurrence of cold cracks in the welds of steel made by means of manual metalarc welding or gasshielded metalarc welding, and also for examining appropriate preheating temperatures for preventing such cold cracks. The test condition and the test results are shown in table 3. This type of damage is also produced during casting. In this paper, a series of theoretical analyses are performed for restraint stressstrain produced in the weld metal of the oblique y groove weld cracking test specimen, varying the kind of steel, heat input, preheating temperature and the base plate thickness. Weld cracking and mechanical properties of 17% chromium. The work detailed in this paper was performed to determine the likelihood of cracking during and after welding of 10 mm thick, high hardness, armour steel plate in conditions of high restraint. In this study, to examine the validity of the crack initiation. Cold cracking susceptibility of the weld metal made with a 16 %cr7 %ni wire was investigated using the y groove weld cracking test. During the y groove selfrestraint cracking test, reheat cracking occurred only in the bismuthcontaining weld metal at temperaturs above 823k during heating or holding.
Ppt seamless flux cored wire powerpoint presentation. Based on this viewpoint, the above effect was examined by y groove restraint cracking test. Schematic illustration of ygroove weld cracking test download. Postheating can be defined as the application of heat to an assembly after welding. Experiences with haz cold cracking tests on a cmn structural steel.
Cn104827170a test weld gap clearance ensuring method in. Download scientific diagram a dimension in mm of ygroove weld cracking test joint, and b experimental photo of ae measurement. Evaluation of hydrogenassisted cracking susceptibility in. Citeseerx the weld cracking susceptibility of high. Cold cracks in the weld metal were measured using the ygroove test, and four different preheating temperatures were employed from room temperature to 150 c. Y groove test is a self restraint test and is best suited. This standard applies primarily but not exclusively to cmn and low alloy steels. Cruciform test controlled thermal severity cts test lehigh restraint test implant test 16. In the development process of a welding wire, the evaluation of cold cracking resistance is important. Test plates were machined in accordance with jis standard z3158 1993 12. The weld cracking susceptibility of high hardness armour.
Critical conditions of cold cracking in high strength. In all the specimens tested, including inclined y groove specimens, cracking was confined to weld metal indicating. In an external weld cracking test, however, stress intensity continues to increase and the. Jfe steel corporation plates high tensile strength. A weld groove is defined as a channel in the surface of a workpiece or an opening.
A groove weld is defined in the american welding society aws aws a3. To make clear the effect of weld thermal cycles during repair welding on the hydrogen content and weld cold cracking at the interface in the structural material of petroleum pressure vessels, the crack susceptibility was estimated by y groove weld cracking test with varying overlay thickness and hydrogen exposure conditions. It suggested that in order to decrease the tendency of welding cracking, the clam steel should be preheated over. C yurioka, kasuya quarterly journal of japan welding society,vol. Penetrant indication after y groove weld cracking test welding conditions jisz3158 y groove weld cracking test welding process. The y groove weld cracking test of ts780mpa grade steel plate was conducted with intentionally introducing hydrogen into the shielding gas during the gasmetal arc welding gmaw. In this study, the effect of lowtemperature transformation expansion on the residual stress reduction of welds with different restraint factors in cold cracking test specimens was examined by. Journal of biomimetics, biomaterials and biomedical engineering materials science. International journal of engineering science and technology vol. Underbead cracking, a typical form of hydrogen induced cracking, was observed in the hardened region of the heat affected zone of ferritic welds where the heat input was 0. Recent developments in weldability testing for advanced. Quarterly journal of the japan welding society steel.
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