Abstract: A first pre-sintered body composed of a powder made of a first Ni-based alloy is prepared, and a second pre-sintered body composed of a powder made of a second Ni-based alloy is prepared. Subsequently, the first and second pre-sintered bodies are positioned to face each other across a predetermined gap, and a joining material made of a Ni-based alloy having a lower liquidus temperature than the first and second Ni-based alloys is placed in a space that adjoins the first and second pre-sintered bodies and to which the gap opens. After the placing of the joining material, the first and second pre-sintered bodies are heated to melt the joining material, fill the gap with the molten joining material, and subsequently turn the first and second pre-sintered bodies into first and second sintered bodies, respectively.

Abstract: A phase shift measuring apparatus for detecting a phase shift of a light wave passing through an object to be measured, including:supplying device for supplying first and second light waves having different frequencies;optical device for directing the first light wave toward the object and combining the first light wave passing through the object and the second light wave to obtain a composite light wave;detecting device for receiving the composite light wave and detecting a measured beat signal; andmeasuring device for comprising the measured beat signal with a predetermined reference beat signal to measure a phase shift of the first light wave.A gradient index, a thickness distribution, and the like of an object can be obtained from the measured phase shift.