Trial Production of Stress Meter of Electrodeposits

Brenner and Senderoff's Contractometer type stress meter was experimentally made reconstructing spiral type thermo regulator. Using this stress meter, the stress of electrodeposits in Watt's type bath was measured. The results is as follows: (1) Errors of stress measurement by this stress meter were within ±5%. (2) Rate of increasing the thickness of electrodeposits owing to decreasing of stress in electrodeposits were almost the same ratio as those published by Kushner or other authorities, and it was confirmed that this phenomenon is caused by increasing grain size of particles of the electrodeposits. (3) Measured electrodeposit stress did not vary largely no matter whether the base metal of spirals was made of steel, copper or brass, of different Young's modulus. (4) Thickness of the spiral of base metal may well be as large as to be enough sensibile to the pointing needle. (5) So far as the surface of base metal of spirals is concerned, in case of the mechanically polished state, the stress was not affected, but in case of the state treated by FeCl3-HCl or other chemical solutions, the first electrodeposit stress was pretty small.