From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Page from a report on strain distribution analysis, referencing Luder's lines and the use of brittle lacquers.
Identifier | ExFiles\Box 142\2\ scan0473 | |
Date | 16th December 1939 | |
6 The preformed lap joint has much less strain and that which it has is distributed up onto the weld instead of being confined to the plate at the weld junction. Plain and corrugated sections of .050 dural sheet with holes in the center and loaded vertically in compression are shown in Figure 6. The elastic buckling of each plate produced the strain patterns seen. The nature of the buckling can be easily reconstructed from the tension strain patterns left in the brittle coatings on the sheets. The unusual pattern in Figure 7 is caused by plastic flow lines, often called "Luder's lines," propagating from a brinell impression in soft steel. They radiate at about 45° to the circular elastic strain patterns, showing that they are connected with the maximum shear stresses. Although many other examples could be sited, these few should indicate the diversity of strain distribution problems in which brittle lacquers may be of aid. 1. Dietrich und Lehr. "Das Dehnungelinierve fahren" Zeitschrift Des Vereines Deutches Ingenieure, Oct. 8 1932. 2. Portevin et Cymboliste, "Procede d'Etude de la{L. A. Archer} Distribution des Efforts Elastiques dans les Pieces Métalliques" Revue de Metallurgie, Vol. 4, April. 1934. ---------- Massachusetts Institute of Technology Cambridge, Massachusetts December 16, 1939 | ||