BUEHLER®

Load 10gf (0.01kgf)
Diagonal Knoop Hardness Number
(µm) 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
52 52.6 52.4 52.2 52.0 51.8 51.6 51.4 51.2 51.0 50.9
53 50.7 50.5 50.3 50.1 49.9 49.7 49.5 49.3 49.2 49.0
54 48.8 48.6 48.4 48.3 48.1 47.9 47.7 47.6 47.4 47.2
55 47.0 46.9 46.7 46.5 46.4 46.2 46.0 45.9 45.7 45.5
56 45.4 45.2 45.1 44.9 44.7 44.6 44.4 44.3 44.1 44.0
57 43.8 43.6 43.5 43.3 43.2 43.0 42.9 42.7 42.6 42.4
58 42.3 42.2 42.0 41.9 41.7 41.6 41.4 41.3 41.2 41.0
59 40.9 40.7 40.6 40.5 40.3 40.2 40.1 39.9 39.8 39.7
60 39.5 39.4 39.3 39.1 39.0 38.9 38.7 38.6 38.5 38.4
61 38.2 38.1 38.0 37.9 37.7 37.6 37.5 37.4 37.3 37.1
62 37.0 36.9 36.8 36.7 36.5 36.4 36.3 36.2 36.1 36.0
63 35.9 35.7 35.6 35.5 35.4 35.3 35.2 35.1 35.0 34.9
64 34.7 34.6 34.5 34.4 34.3 34.2 34.1 34.0 33.9 33.8
65 33.7 33.6 33.5 33.4 33.3 33.2 33.1 33.0 32.9 32.8
66 32.7 32.6 32.5 32.4 32.3 32.2 32.1 32.0 31.9 31.8
67 31.7 31.6 31.5 31.4 31.3 31.2 31.1 31.0 31.0 30.9
68 30.8 30.7 30.6 30.5 30.4 30.3 30.2 30.2 30.1 30.0
69 29.9 29.8 29.7 29.6 29.5 29.5 29.4 29.3 29.2 29.1
70 29.0 29.0 28.9 28.8 28.7 28.6 28.5 28.5 28.4 28.3
71 28.2 28.1 28.1 28.0 27.9 27.8 27.8 27.7 27.6 27.5
72 27.4 27.4 27.3 27.2 27.1 27.1 27.0 26.9 26.8 26.8
73 26.7 26.6 26.6 26.5 26.4 26.3 26.3 26.2 26.1 26.1
74 26.0 25.9 25.8 25.8 25.7 25.6 25.6 25.5 25.4 25.4
75 25.3 25.2 25.2 25.1 25.0 25.0 24.9 24.8 24.8 24.7
76 24.6 24.6 24.5 24.4 24.4 24.3 24.3 24.2 24.1 24.1
77 24.0 23.9 23.9 23.8 23.8 23.7 23.6 23.6 23.5 23.4
78 23.4 23.3 23.3 23.2 23.2 23.1 23.0 23.0 22.9 22.9
79 22.8 22.7 22.7 22.6 22.6 22.5 22.5 22.4 22.3 22.3
80 22.2 22.2 22.1 22.1 22.0 22.0 21.9 21.9 21.8 21.7
81 21.7 21.6 21.6 21.5 21.5 21.4 21.4 21.3 21.3 21.2
82 21.2 21.1 21.1 21.0 21.0 20.9 20.9 20.8 20.8 20.7
83 20.7 20.6 20.6 20.5 20.5 20.4 20.4 20.3 20.3 20.2
84 20.2 20.1 20.1 20.0 20.0 19.9 19.9 19.8 19.8 19.7
85 19.7 19.6 19.6 19.6 19.5 19.5 19.4 19.4 19.3 19.3
86 19.2 19.2 19.2 19.1 19.1 19.0 19.0 18.9 18.9 18.8
87 18.8 18.8 18.7 18.7 18.6 18.6 18.5 18.5 18.5 18.4
88 18.4 18.3 18.3 18.3 18.2 18.2 18.1 18.1 18.0 18.0
89 18.0 17.9 17.9 17.8 17.8 17.8 17.7 17.7 17.6 17.6
90 17.6 17.5 17.5 17.5 17.4 17.4 17.3 17.3 17.3 17.2
91 17.2 17.1 17.1 17.1 17.0 17.0 17.0 16.9 16.9 16.8
92 16.8 16.8 16.7 16.7 16.7 16.6 16.6 16.6 16.5 16.5
93 16.5 16.4 16.4 16.3 16.3 16.3 16.2 16.2 16.2 16.1
94 16.1 16.1 16.0 16.0 16.0 15.9 15.9 15.9 15.8 15.8
95 15.8 15.7 15.7 15.7 15.6 15.6 15.6 15.5 15.5 15.5
96 15.4 15.4 15.4 15.3 15.3 15.3 15.2 15.2 15.2 15.2
4