Investigation of the Effect of Tool Temperature on Microstructure, Hardness, and Wear Behaviour of Aluminium 6061-T6 Alloy Welded by the Friction Stir Welding Process

Table 2

Material hardness and different tool temperatures.

Tool temperature	(40.5°C)	(46°C)	(54°C)
Test 1	63 HV	77.4	91.3
Test 2	72.4 HV	78.3	89.1
Test 3	75.7 HV	70.9	82.1
Mean	70.4 HV	75.5 HV	87.5 HV
Standard deviation	6.6	4.0	4.8
Error bars	3.8	2.3	2.8