1012 THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1953 



Nye, J. F. ' 



Some Geometrical Relations in Dislocated Crystals, Acta Metallur- 

 gica, 1, pp. 153-162, Mar., 1953. 



When a single crystal deforms by glide which is unevenly distributed over the 

 glide surfaces the lattice becomes curved. The constant feature of distortion 

 by gUde on a single set of planes is that the orthogonal trajectories of the de- 

 formed gUde planes (the c-axes in hexagonal metals) are straight lines. This 

 leads to the conclusion that in polygonisation experiments on single hexagonal 

 metal crystals the polygon walls are planes, while the glide planes are de- 

 formed into cyhnders whose sections are the involutes of a single curve. The 

 analysis explains West's observation that c-axes in bent crystals of corundum 

 are straight lines. For double glide on two orthogonal sets of planes there is a 

 complete analogy between the geometrical properties of the distorted ghde 

 planes and those of the "slip-lines" in the mathematical theory of plasticity. 

 More general cases are discussed and formulae are derived connecting the 

 density of dislocations with the lattice curvatures. For a three-dimensional 

 network of dislocations the "state of dislocation" of a region is shown to be 

 specified by a second-rank tensor, which has properties like those of a stress 

 tensor except that it is not symmetrical. 



O'Connor, S. F.' 



Plating Room Waste Water Disposal, Metal Finishing, 51, pp. 56- 

 58, Feb., 1953. 



Olsen, K. M., see W. G. Pfann. 



Owens, C. D.' 



Analysis of Measurements on Magnetic Ferrites, I.R.E., Proc, 41, 

 pp. 359-365, Mar., 1953 (Monograph 2075). 



The unconventional behavior of permeability and core loss in the magnetic 

 ferrites as compared to metals has led to a study of core-loss measurements. 

 The relationships between the magnetic quality factor nQ and the charac- 

 teristics of coils and transformers are developed, and the advantages of /xQ 

 as a parameter for the study and application of ferrites are discussed. A selec- 

 ted bibliography is given. 



Pfann, W. G.,^ and K. M. Olsen^ 



Purification and Prevention of Segregation in Single Crystals of 

 Germanium, Letter to the Editor, Phys. Rev., 89, pp. 322-323, Jan. 

 1, 1953. 



• Bell Telephone Laboratories, Inc. 

 » Western Electric Company. 



