US 12,246,390 B2
Friction stir welding tool insert
Santonu Ghosh, Oxfordshire (GB); and Stig Åke Andersin, Oxfordshire (GB)
Assigned to Element Six (UK) Limited, Oxfordshire (GB)
Appl. No. 18/043,375
Filed by Element Six (UK) Limited, Oxfordshire (GB)
PCT Filed Sep. 1, 2021, PCT No. PCT/EP2021/074114
§ 371(c)(1), (2) Date Feb. 28, 2023,
PCT Pub. No. WO2022/049113, PCT Pub. Date Mar. 10, 2022.
Claims priority of application No. 2013686 (GB), filed on Sep. 1, 2020.
Prior Publication US 2023/0311240 A1, Oct. 5, 2023
Int. Cl. B23K 20/12 (2006.01)
CPC B23K 20/1255 (2013.01) 18 Claims
OG exemplary drawing
 
1. A friction stir welding (FSW) tool insert having a longitudinal axis of rotation, said tool insert comprising:
a stirring pin; and
an annular shoulder coaxially mounted about the stirring pin, the stirring pin and annular shoulder each comprising polycrystalline cubic boron nitride,
wherein the annular shoulder is a thin disc with a thickness of 1 to 12 mm and wherein the shoulder comprises a tapered, central aperture, through which the stirring pin protrudes,
wherein the stirring pin comprises a conical first pin portion extending away from a second pin portion at a boundary, towards an apex, wherein the second pin portion
comprises an outwardly tapering waist section proximate the boundary, the waist section extending into an outwardly tapering middle section, the middle section extending into an inwardly tapering base section.