Study on the tensile properties and deformation mechanism of high-temperature resistant nitrogen-containing nickel-based welding material deposited metal

This article uses a new type of nitrogen-containing nickel-based flux cored welding wire as the experimental material to study the tensile properties and deformation mechanism of the deposited metal from room temperature to 900 degrees C. The results show that the tensile strength gradually decreases with the temperature. The plasticity gradually increases, but the lowest value appears at 700 degrees C, which is the phenomenon of intermediate temperature brittleness. M23C6 carbides begin to decompose at 700 degrees C. More carbonitrides are precipitated within the crystal with temperature. In the low-temperature zone (T <= 600 degrees C), the main deformation mechanism is the unit dislocation a/2<110> cutting precipitation phase. In the medium-temperature zone (600 degrees C < T <= 750 degrees C), initiation of Orowan bypass mechanism for dislocations. In the high-temperature zone (800 degrees C <= T <= 900 degrees C), the slip and climbing mechanism of dislocation is the main deformation mechanism.