Influence of Electron Beam Welding Parameters on the Microstructure Formation and Mechanical Behaviors of the Ti and Ni Dissimilar Metals Welded Joints

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21220%2F22%3A00359840" target="_blank" >RIV/68407700:21220/22:00359840 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.3390/met12060894" target="_blank" >https://doi.org/10.3390/met12060894</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/met12060894" target="_blank" >10.3390/met12060894</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Influence of Electron Beam Welding Parameters on the Microstructure Formation and Mechanical Behaviors of the Ti and Ni Dissimilar Metals Welded Joints

Popis výsledku v původním jazyce

Commercially pure titanium Ti Grade 2, 2 mm in thickness, was welded to 2 mm thick nickel alloy 201 with electron beam welding. Various welding parameters were used to create the butt-welded joints. The innovation herein consists of welding two dissimilar metals that are declared non-weldable. The welding current used for electron beam welding was 40–70 mA and welding speeds were 20–50 mm/s. In this experiment, we tested two offsets of the electron beam, which were 100–300 μm to the nickel side and 200 μm to the titanium side. It was observed that the offset of the beam had no effect on the weld joint’s strength. The samples were subjected to a visual test in which longitudinal and transverse cracks were recorded along the whole weld. Only four samples retained the integrity of the joint. Microstructures of the weld joints were examined by scanning confocal and scanning electron microscopy. Energy dispersive spectroscopy (EDS) analysis confirmed the phase constitution inside the weld regions and the fusion interfaces. Tensile strength and microhardness tests were used to evaluate the mechanical parameters of the Ti/Ni welded joint. The results showed that cracking of brittle Ni–Ti intermetallic phases in electron beam welded joints occurred. The microstructure in the fusion zone’s center part was primarily NiTi and Ti2Ni. No clear correlation was found between heat input or welding parameters—welding current and welding speed—and tensile strength. The strain–tensile strength curve resulted in brittle fracturing. The hardness of the weld zone was five times higher than that of the base metal and heat-affected zone. The amount of heat input into the welded metal is as critical as the large asymmetry in heat transport that controls the process of solidification from each side of the base metal.

Název v anglickém jazyce

Influence of Electron Beam Welding Parameters on the Microstructure Formation and Mechanical Behaviors of the Ti and Ni Dissimilar Metals Welded Joints

Popis výsledku anglicky

Commercially pure titanium Ti Grade 2, 2 mm in thickness, was welded to 2 mm thick nickel alloy 201 with electron beam welding. Various welding parameters were used to create the butt-welded joints. The innovation herein consists of welding two dissimilar metals that are declared non-weldable. The welding current used for electron beam welding was 40–70 mA and welding speeds were 20–50 mm/s. In this experiment, we tested two offsets of the electron beam, which were 100–300 μm to the nickel side and 200 μm to the titanium side. It was observed that the offset of the beam had no effect on the weld joint’s strength. The samples were subjected to a visual test in which longitudinal and transverse cracks were recorded along the whole weld. Only four samples retained the integrity of the joint. Microstructures of the weld joints were examined by scanning confocal and scanning electron microscopy. Energy dispersive spectroscopy (EDS) analysis confirmed the phase constitution inside the weld regions and the fusion interfaces. Tensile strength and microhardness tests were used to evaluate the mechanical parameters of the Ti/Ni welded joint. The results showed that cracking of brittle Ni–Ti intermetallic phases in electron beam welded joints occurred. The microstructure in the fusion zone’s center part was primarily NiTi and Ti2Ni. No clear correlation was found between heat input or welding parameters—welding current and welding speed—and tensile strength. The strain–tensile strength curve resulted in brittle fracturing. The hardness of the weld zone was five times higher than that of the base metal and heat-affected zone. The amount of heat input into the welded metal is as critical as the large asymmetry in heat transport that controls the process of solidification from each side of the base metal.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20301 - Mechanical engineering

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Metals — Open Access Metallurgy Journal

ISSN

2075-4701

e-ISSN

2075-4701

Svazek periodika

12

Číslo periodika v rámci svazku

6

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

18

Strana od-do

—

Kód UT WoS článku

000818260900001

EID výsledku v databázi Scopus

2-s2.0-85130808573