Thermoelectric Force of Nickel

Thermoelectric Force of Nickel against Platinum, Lead, Silver, and Copper.

The thermoelectric force of a couple of nickel and platinum, for 100°, was found by J. Dewar and J. A. Fleming to be -1.43 millivolts; by K. Feussner and St. Lindeck, -1.20 millivolts; G. Reichard, -1.94 millivolts; E. Wagner, -1.52 millivolts; K. Noll, -1.65 millivolts; W. Jager and H. Diesselhorst, -1.62 millivolts; and P. W. Bridgman, -1.496 millivolts - vide Fig. Nickel is thermoelectrically negative to platinum so that in a simple thermoelectric circuit of these two metals, the current flows from platinum to nickel at the cold junction.

The Thermoelectric Force of the Ni-Pt Couple.

K. E. Grew's results are plotted in Fig., and they show a striking break in the curve at 360°. W. H. Ross studied the effect of longitudinally and transversely magnetized wires. Observations were made by K. E. Grew, W. Rohn, and F. E. Bash - vide Fig. F. R. Caldwell found the e.m.f., E millivolts, of 99.94 per cent, nickel against platinum to be:

	100°	200°	300°	400°	500°	700°	900°	1100°
E	1.485	3.105	4.590	5.450	6.165	8.105	10.695	13.625

Thermoelectric Force of Nickel and its Alloys against Platinum.

Thermoelectric Force of Nickel and its Alloys against Copper.

The results are plotted in Fig.; there is a change in the direction of the curve in the region of the magnetic transformation. The results of W. Rohn are summarized in Fig. The temp, coeff. of the thermoelectric force obtained by J. Dorfmann and R. Jaanus are indicated in Fig. K. E. Grew studied the thermoelectric effect at the Curie point of nickel; and G. Tammann and G. Bandel, the efEect of cold-work. L. Jordan and W. H. Swanger gave 1.485 millivolts at 100°, 6.165 millivolts at 580°, and 12.130 millivolts at 1000°. L. Holborn and co-workers gave for the thermoelectric force, E millivolts, couples of nickel and tungsten, and of nickel and iron:

	0	100°	200°	300°	400°	600°	800°	1000°	1100°
E(W)	0.00	2.43	5.45	8.73	11.68	18.36	27.36	-	-
E(Fe)	0.00	-	-	9.2	10.7	13.1	17.2	21.5	23.7

Thermoelectric Force of Nickel against other Metals

E. P. Harrison found that with the iron-nickel couple E=-5.08 at -185°; zero at 0°; 3.13 at 100°; 6.16 at 200°; 11.81 at 500°; and 15.01 at 700°. H. Broili, and W. Gerlach studied the thermomagnetic effect of iron and nickel. Observations were also made by E. F. Northrup, J. Monheim, H. Lent and F. Kofler, and M. A. Hunter and H. Jones - vide Fig. L. Peckinger measured the effect of varying the diameter of the wires of the thermocouple. E. Rudolfi, H. Pecheux, A. W. Foster, J. J. McHenry, T. H. Pi and W. Band, and A. Krupkowsky measured the thermoelectric force of the couple of nickel and copper. J. E. Schrader studied the effect of heat treatment; and E. Dubois found that the effect against copper becomes electronegative after the metal has been heated and cooled. W. M. Latimer, and G. von Hevesy and E. Wolff gave for a couple of nickel and silver – Fig.; R. von Dallwitz-Wegner gave -0.0015 volt at 100° for the nickel and constantan couple; C. Dannecker, for couples of nickel and nickel silver, and of nickel and cobalt, Fig.; C. R. Darling and A. W. Grace, bismuth and nickel; and F. Hoffmann and A. Schulze, for a couple of nickel and carbon:

Ni+	-185°	-80°	0°	100°	200°	400°	600°	800°	1000°	1200°
Ag	-	-1.68	0	-2.18	4.96	9.85	14.5	20.73	-	-
Ni-Ag	-0.5	-0.4	0	0.6	1.1	0.4	-2.5	-5.1	-	-
Co	-	-	0	-0.3	-1.3	-4.6	-8.7	-10.4	-	-
C	-	-	0	2.20	4.61	8.82	12.9	18.7	26.1	34.8

J. Dewar and J. A. Fleming's results for nickel against lead are shown in Fig.; and observations at low temp, were made by G. Weitzel. W. Rohn's results for nickel against tungsten, molybdenum, tantalum, aluminium, magnesium, iron, and gold are summarized in Fig.; P. W. Bridgman represented the thermoelectric force E, of nickel against lead, by E×10⁶=17.61θ – 0.0178θ² volts. He also found for the thermoelectric force. E×10⁶ volts, of a couple of uncompressed nickel and of nickel compressed at a press, p kgrms. per sq. cm.:

	10°	20°	40°	60°	80°	100°
2,000	0.12	0.25	0.54	0.87	1.25	1.68
6,000	0.41	0.85	1.82	2.88	4.02	5.24
12,000	0.91	1.99	4.00	6.32	8.81	11.44

E. Wagner gave for 300 kgrms. per sq. cm. press, between 0° and 100°, 9.6×10^-12 volt per degree per kilogram. H. Tomlinson observed that a decrease in the thermoelectric force is produced by longitudinal traction. P. W. Bridgman obtained for the e.m.f., E×10⁶ volts, of a couple with unloaded nickel and of nickel in tension under a load of τ kgrms. per sq. cm., E×10⁶=0.00335τ – 0.0₆60τ² volts at 31°; E×10⁶=0.00577τ – 0.0₅132τ² volts at 51°; E×10⁶=0.0081τ - 0.0₅175τ² volts at 77.5°; and E×10⁶=0.0121τ – 0.0₅37τ² volts at 94.5°. M. Maclean found for a couple of nickel wires, one of which was permanently stretched longitudinally, an e.m.f. of 0.1341 microvolt per degree difference of temp, between the hot and cold junctions when the current passed from the stretched to the unstretched wire. W. del Regno observed a break in the thermoelectric power near 400°. H. Pecheux studied the effect of impurities on the thermoelectric force of nickel; H. Pelabon found that the thermoelectric power varies continuously through the m.p.; and G. Weitzel investigated the effect at a low temp. The thermoelectric properties of nickel were also studied by T. Tsutsui, and P. N. Laschtschenko and co-workers; A. Perrier and T. Kousmine, between magnetized and non-magnetized nickel; and the contact e.m.f. between solid and liquid nickel, by P. H. Dowling; the thermoelectric force between annealed and strain-hardened metal, by L. J. Newman; the effect of ageing, by J. Thiele ; the effect of cold-work, by G. Tammann ; the decrease in the thermoelectric force by magnetization, by H. Tomlinson, W. H. Boss, S. R. Williams, and S. Seass.