Rotor and method for welding an element of a rotor

A method of forming a rotor comprising the steps of:

• removing at least a portion of a creep-life expired region of a first rotor element, the first rotor element formed from a steel;
• replacing the removed portion of the first rotor element by welding the rotor element with a weld metal or by welding a second rotor element to the first rotor element with the weld metal, the weld metal comprising 0.04 to 0.1% carbon, 0 to 0.5% silicon, 0.1 to 0.6% manganese, 0 to 0.1% sulphur, 0 to 0.03% phosphorous, 1.9 to 2.6% chromium, 0.05 to 0.3% molybdenum, 0.2 to 0.3% vanadium, 0.02 to 0.08% niobium, 1.45 to 2.1% tungsten, 0 to 0.03% nitrogen, 0.0005 to 0.006% boron, and 0 to 0.03% aluminium, remainder iron;
• heat treating the rotor at a temperature range of 650° C. to 750° C.;
• and
• machining the rotor to remove at least a portion of the weld metal.