Intravascular devices, systems, and methods having a core wire formed of multiple materials

A sensing guide wire, comprising:

• a core member comprising an inner section and an outer section surrounding the inner section, wherein the inner section is formed of a first material and the outer section is formed of a second material that is different than the first material;
• a single outer layer surrounding the core member;
• a flexible element coupled to a distal portion of the core member;
• a sensing element adjacent to the flexible element;
• a connector coupled to a proximal portion of the sensing guide wire;
• and
• at least one communication line embedded within the single outer layer such that the at least one communication line and the core member are isolated by the single outer layer,
• wherein the single outer layer is directly in contact with both the core member and the at least one communication line,
• wherein the sensing element is communicatively coupled to the connector via the at least one communication line, and
• wherein the at least one communication line comprises an exposed section at a distal portion of the sensing guide wire, wherein the exposed section is exposed by removal of a portion of the single outer layer at the distal portion of the sensing guide wire, and wherein the sensing element is electrically coupled to the at least one communication line by an electrical coupling between the exposed section and the at least one communication line.