OCR Text |
Show I Itemarlcnblc litTects onions on Steel. Specimens of stcol of thrco dlfforont qualities, depending on a varying proportion pro-portion of carbon, havo boon tested in Germany to dctcrmino tho chango in their strength with chango In tempera-I tempera-I ture. Starting from four degrees below zozo Fnhrohoit, tho test pieces diminished dimin-ished both in strength and percentage of elongation up to u temperaturo be-tweon be-tweon 400 and COO dogrccs, then roso to a maximum at about COO decrees and foil steadily beyond that point up to 1,100 degrees, the highest tomporaturo tried. At COO degrees tho strength of tho weakest bar supporting twenty-six twenty-six tons at ordinary temperatures was increased 34 per cent that of tho soc-ond soc-ond bar usually sustaining twenty-soven twenty-soven tons and rlson i!7 per cent and, that of tho third bar of an ordinary strength of thlrty-ono tons had gained 25 por cent. |