112 DEPARTMENT BULLETIN 1216, U. S. DEPT. OF AGRICULTURE 
of taking samples from which to prepare test specimens are treated in the indi- 
vidual specifications for ferrous metals and for nonferrous metals. 
TEST SPECIMENS 
1. In recommending the following specimens for use in tension tests it is not 
intended to exclude entirely the use of other test specimens for special materials 
or for special forms of material ; for example, in tests of tubing and pipe the 
form of specimen recommended for plate, shape, and flat material (fig. 48) is 
not generally suitable for use and a special form of specimen is specified. It is, 
however, recommended that wherever it is feasible the specimens here recom- 
mended be used. 
k- Parallel Section not less than 9" — ->l |*« About 3*> 
ftf 
~ J^~ 
yr~ 
A ys> 
About 2 
~> L 
II 
{<- 8 Gage Length — ----- ->| / 
for Measuring Elongation *> ^ 
after Fracture X^ & 
t - Thickness of Plate 
Fig. 48. — Tension test specimen for plate material 
2. Tension test specimens of wire are of the full-size diameter as drawn, and 
tension test specimens of rods of ductile metal are often of the full-size diameter 
as rolled. Tension test specimens of pipe and of tubing are frequently of full 
size as manufactured, in which case the ends should be plugged with metal 
plugs which do not extend within the gauge marks. 
3. The tension test specimen shown in Figure 48 is recommended for plate, 
shape, and flat material having a thickness of one-fourth inch or over. 5 * The 
thickness of the specimen is that of the material tested. 
(a) Ends not symmetrical with reduced 
section 
- f=*= 
E3- 
(6) Two sides of reduced section not 
symmetrical 
■E 
>-/" 
h 
(c) Ends not parallel to reduced 
section 
(d) Narrow width due to " hogging in " 
of cutter 
Fig. 49. — Common errors in preparation of plate or sheet-metal test specimens 
Note. — When it is desired to use a specimen, with a gauge length of less than 8 inches, 
the general proportions of Figure 48 should be followed. Specimens with a gauge length 
of 2 inches are occasionally used. When it is not convenient to machine specimens to the 
standard shape shown in Figure 48, specimens may be used with edges machined parallel 
for the entire length of the specimen. If such specimens are machined with a tool cutting 
across the edges of the specimen, it is important that the transverse tool marks be 
removed before the specimen is tested. For thick plate material it is usually preferable 
to use a machine specimen rather than to use a specimen the full thickness of the plate. 
4. For tension tests of wrought ferrous and nonferrous metal in the form 
of plate, sheet, flat wire, 55 strip, 55 band, 55 and hoop 65 without respect to 
width. 55 length, grade, or method of manufacture, and having a thickness from 
0.01 to 0.250 inch, the tost specimen described in sections 5 and 6 is recom- 
mended. 56 
54 Attention is called to the fact that two types of specimen are applicable for material 
one-fourth inch in thickness, the plate specimen shown in Figure 48, and the thin sheet 
specimen shown in Figure 50. 
55 It is to be noted that the recommended specimen can not be used for flat wire, strip, 
band, or hoop material whose width is less than the end width of the specimen itself. 
66 This specimen may also be used in tests of material cut from tubing. 
