WKOUGHT IBON.
442
No. 7438.
Burden’s Best Iron. Diameter, 1".129.
Sectional area, 1 square inch. Gauged length, 10".
Remarks.
Load sustained 5 minutes.
Do.
Do.
Do.
Elastic limit.
Sustained one-half minute, then rapid elongation.
Applied loads per square inch.	In gauged length.	
	Elonga- tion.	Set.
Pounds.	Inches.	Inch.
1,000	0.	0.
5,000	.0012	0.
10,000	.0031	
20,000	.0067	0.
26,000	.0089	
26,500	.0091	
27,000	.0093	
27,500	.0096	
28,000	.0098	
25,000 ■j	.0170 .0190	
26,000	.0350	
27,000	.0760	
28,000	.1700	
29,000	.1900	
30,000	. 2225	.2100
32,000	.29	
34,000	.36	
36,000	.44	
38,000	.54	
40,000	.69	.67
Rested without load 51 days.
Micrometer reset at zero on 8" of the original gauged length.
Second application of load.
0.
0.
-.0002
-.0002
+.0001
.0850
.1540
0.
.0014
. 0062 . 0094 .0126 .0139 .0145 .0146 .0152 .0166 .1000 .1690
1,000 5,000 10,000 20,000
30.000
40.000
44.000
45.000
45.000
46.000
47.000 47,100
48.000
Tensile strength. =25.2 per cent.
.90 .94 1.03 1.13 1.30 1.68 2.52
48.000
49.000
50.000
51.000
52.000 52,800
0
Elongation of inch sections: ".16, ".19, ".25, ".27, ".25, ".55*, ".30, ".20, ".19, ".16.
Diameter at fracture, ".84; area, .554 square inch.
Contraction of area, 44.6 per cent.
Appearance of fracture, fibrous.