Tool for friction stir welding, method of welding with the same, and processed object obtained by the same

A friction stir welding tool which can friction-stir-weld a metal or alloy having a high melting point of 1350° C. or more as an object to be worked, wherein

• at least a portion of the tool brought into contact with the object to be worked is formed by a ternary alloy comprising iridium, 1.0 to 35.0 atomic percentages of molybdenum, and 0.1 to 5.0 atomic percentages of zirconium, hafnium, lanthanum, cerium, samarium, gadolinium, scandium, or yttrium, and
• wherein the friction stir welding tool has a Micro Vickers Hardness of 300 Hv or more.

A friction stir welding tool which can friction-stir-weld a metal or alloy having a high melting point of 1350° C. or more as an object to be worked, wherein

• at least a portion of the tool brought into contact with the object to be worked is formed by a ternary alloy comprising iridium, 1.0 to 25.0 atomic percentages of niobium or tantalum, 0.1 to 5.0 atomic percentages of zirconium, hafnium, lanthanum, cerium, samarium, gadolinium, scandium, or yttrium, and
• wherein the friction stir welding tool has a Micro Vickers Hardness of 300 Hv or more.

A friction stir welding tool which can friction-stir-weld a metal or alloy having a high melting point of 1350° C. or more as an object to be worked, wherein

• at least a portion of the tool brought into contact with the object to be worked is formed by a quaternary alloy comprising iridium, 1.0 to 50.0 atomic percentages of rhenium or ruthenium, 1.0 to 18.0 atomic percentages of rhodium, and 0.1 to 5.0 atomic percentages of zirconium, hafnium, lanthanum, cerium, samarium, gadolinium, scandium, or yttrium, and
• wherein the friction stir welding tool has a Micro Vickers Hardness of 300 Hv or more.

A friction stir welding tool which can friction-stir-weld a metal or alloy having a high melting point of 1350° C. or more as an object to be worked, wherein

• at least a portion of the tool brought into contact with the object to be worked is formed by a quaternary alloy comprising iridium, 1.0 to 35.0 atomic percentages of molybdenum or tungsten, 1.0 to 18.0 atomic percentages of rhodium, and 0.1 to 5.0 atomic percentages of zirconium, hafnium, lanthanum, cerium, samarium, gadolinium, scandium, or yttrium, and
• wherein the friction stir welding tool has a Micro Vickers Hardness of 300 Hv or more.

A friction stir welding tool which can friction-stir-weld a metal or alloy having a high melting point of 1350° C. or more as an object to be worked, wherein

• at least a portion of the tool brought into contact with the object to be worked is formed by a quaternary alloy comprising iridium, 1.0 to 25.0 atomic percentages of niobium or tantalum, 1.0 to 18.0 atomic percentages of rhodium, and 0.1 to 5.0 atomic percentages of zirconium, hafnium, lanthanum, cerium, samarium, gadolinium, scandium, or yttrium, and
• wherein the friction stir welding tool has a Micro Vickers Hardness of 300 Hv or more.

A friction stir welding tool which can friction-stir-weld a metal or alloy having a high melting point of 1350° C. or more as an object to be worked, wherein

• at least a portion of the tool brought into contact with the object to be worked comprises at least iridium and rhodium, and a content of rhodium is 1.0 to 18.0 atomic percentages, and
• wherein the friction stir welding tool has a Micro Vickers Hardness of 300 Hv or more.

A friction stir welding tool which can friction-stir-weld a metal or alloy having a high melting point of 1350° C. or more as an object to be worked, wherein at least a portion of the tool brought into contact with the object to be worked is formed by a ternary alloy comprising iridium, 5.0 to 35.0 atomic percentages of tungsten, and 0.1 to 5.0 atomic percentages of zirconium, hafnium, lanthanum, cerium, samarium, gadolinium, scandium, or yttrium, and wherein the friction stir welding tool has a Micro Vickers Hardness of 300 Hv or more.