There is provided a method of joining a first member made of a niobium titanium alloy to a second member. The method comprises abutting a respective surface of each of the first member and the second member together to form an interface therebetween; providing a molten active solder at a surface of at least the first member at the interface and thermally activating the molten active solder; mechanically agitating the molten active solder so as to cause the molten solder to adhere to the first and second members and form a continuous body of molten solder linking the first and second; and causing the continuous body to solidify thereby forming a solder joint between the first and second members.