A thermocouple cable, comprising: a first conductor and a second conductor, wherein the first conductor and the second conductor extend within a composite sheath; the composite sheath comprising a metal alloy outer sheath and a nickel-based inner sheath positioned between the first conductor and the second conductor and the metal alloy outer sheath; wherein the first conductor and the second conductor form a weld bead hot junction at the end of the thermocouple cable, a cap positioned at an end of the thermocouple cable at a weld-closure area of the thermocouple cable or a closure positioned at an end of the thermocouple cable, characterized in that the cap comprises: a) an external portion matching an outer sheath material and an internal portion matching an inner sheath material; or b) an external cap positioned at an end of the thermocouple cable at the weld-closure area of the thermocouple cable, wherein the external cap is made from a same material as the outer sheath and an internal cap positioned at an end of the thermocouple cable at the weld-closure area of the thermocouple cable, wherein the internal cap is made from a same material as the inner sheath; or c) a single pressed cap positioned at an end of the thermocouple cable at the weld-closure area of the thermocouple cable and further wherein the single pressed cap includes a top half made from a same material as the outer sheath and a bottom half made from a same material as the inner sheath; or wherein the closure is d) a cold swaged sheath closure positioned at an end of the thermocouple cable and further wherein the cold swaged sheath closure includes a top half made from a same material as the outer sheath and a bottom half made from a same material as the inner sheath. a first conductor and a second conductor, wherein the first conductor and the second conductor extend within a composite sheath; the composite sheath comprising a metal alloy outer sheath and a nickel-based inner sheath positioned between the first conductor and the second conductor and the metal alloy outer sheath; wherein the first conductor and the second conductor form a weld bead hot junction at the end of the thermocouple cable, a cap positioned at an end of the thermocouple cable at a weld-closure area of the thermocouple cable or a closure positioned at an end of the thermocouple cable, a) an external portion matching an outer sheath material and an internal portion matching an inner sheath material; or b) an external cap positioned at an end of the thermocouple cable at the weld-closure area of the thermocouple cable, wherein the external cap is made from a same material as the outer sheath and an internal cap positioned at an end of the thermocouple cable at the weld-closure area of the thermocouple cable, wherein the internal cap is made from a same material as the inner sheath; or c) a single pressed cap positioned at an end of the thermocouple cable at the weld-closure area of the thermocouple cable and further wherein the single pressed cap includes a top half made from a same material as the outer sheath and a bottom half made from a same material as the inner sheath; or wherein the closure is d) a cold swaged sheath closure positioned at an end of the thermocouple cable and further wherein the cold swaged sheath closure includes a top half made from a same material as the outer sheath and a bottom half made from a same material as the inner sheath.