... helium. It is 20 CRC Handbook of Lubrication FIGURE 3.Planes of possible slip in a cubiccrystal; (a) three (10 0) planes, (b) six (11 0) planes,and (c) four (11 1) planes.Copyright © 19 83 CRC Press ... Physics of Materials, Materials Science Series, Vols. 1 and 2, AcademicPress, 19 75. 10 . Somoraji, G. A., Principles of Surface Chemistry, Prentice-Hall, Englewood Cliffs, N.J., 19 72. 11 . Proc. 2nd ... adjacent (11 1) planes is least and the surface energy of new (11 1) surfaces generated, say by cleavage,is less than for the (11 0) and (10 0) planes. This lesser binding strength is also a functionof...