Table I
Conditions of excitation and developing.
1. Light source | High voltage a.c. spark |
2. Upper electrode | Steel sample |
3. Lower electrode | Graphite |
4. Lower electrode tip | Spherical end (
radius) |
5. Gap spacing | 3 mm |
6. Secondary capacity | 0.007 microfarad |
7. Inductance | 0.182 millihenry |
8. Power |
kva |
9. Pre-spark | 40 sec. |
10. Exposure | Steel—10 sec. |
| Cast iron—15 sec. |
11. Slit width | 62 microns |
12. Air blast pressure | 0.5 pound on gauge |
13. Film | Eastman’s spectrum, anal. No. 1 |
14. Developer | D-19 (3 minutes) |
15. Rinse bath | Acetic acid sol. |
16. Fixer | Eastman x-ray fixer |
17. Dryer | Infra-red lamp (1 min. 10 sec.) |
Table II
Element and internal standard lines.
Element line | Internal standard | Material | Concentration ranges (%) |
---|
Mn 3474.133 | Fe 3205.4 | Steel | 0.35–2.00 |
Cr 2971.906 | Fe 3205.4 | Steel | 0.20–1.80 |
Ni 3050.819 | Fe 3205.4 | Steel | 0.20–3.75 |
Mo 3170.347 | Fe 3205.4 | Steel | 0.10–1.00 |
Si 2881.578 | Fe 3205.4 | Steel | 0.10–0.60 |
Al 3082.155 | Fe 3205.4 | Steel | 0.40–1.40 |
Cu 3273.962 | Fe 3205.4 | Steel | 0.05–0.20 |
V 3110.706 | Fe 3205.4 | Steel | 0.04–0.25 |
Mn 2933.063 | Fe 2880.827 | Cast iron | 0.30–1.00 |
Si 2881.578 | Fe 2880.827 | Cast iron | 1.00–2.50 |
Wave-lengths as given in M.I.T. wave-length tables.
Table III
Effect of size of sample.
Test No. | Sample | Si | Mn | Cr | Ni | Mo |
---|
1. |
| 0.42 | 1.12 | 0.25 | 0.30 | 0.11 |
|
| .42 | 1.12 | .27 | .31 | .115 |
|
| .43 | 1.14 | .26 | .31 | .11 |
|
| .43 | 1.12 | .26 | .31 | .11 |
2. | Large forging | 0.21 | 0.84 | | | |
| Small sample | .21 | .85 | | | |
Table IV
Effect of variations of atmospheric condition on analysis of 1.80% Ni, 0.68% Mn steel.
Temperature | Rel. humidity | Exposure | Nickel | Manganese |
---|
76°F | 50% | Normal | 1.80% | 0.67% |
85°F | 75% | Light | 2.01% | .73% |
85°F | 75% | Normal | 1.95% | .73% |
Percentages shown are averages of four tests under each condition.
Table V
Reproducibility tests, A4340 steel.
Type and date of analysis | Test No. | Mo % | Ni % | Cr % | Si % | Mn % |
---|
Wet analysis | 1 | 0.28 | 1.80 | 0.65 | 0.27 | 0.68 |
Spect. analysis |
8–17–43 | 1 | .28 | 1.79 | .65 | .27 | .67 |
| 2 | .30 | 1.82 | .65 | .29 | .69 |
8–18–43 | 3 | .29 | 1.83 | .67 | .29 | .70 |
| 4 | .28 | 1.83 | .65 | .29 | .69 |
8–19–43 | 5 | .28 | 1.82 | .64 | .27 | .68 |
| 6 | .28 | 1.76 | .63 | .27 | .69 |
| 7 | .28 | 1.79 | .65 | .26 | .69 |
| 8 | .28 | 1.82 | .63 | .26 | .69 |
8–20–43 | 9 | .28 | 1.75 | .65 | .26 | .69 |
| 10 | .28 | 1.84 | .63 | .26 | .66 |
8–21–43 | 11 | .27 | 1.82 | .62 | .27 | .67 |
| 12 | .27 | 1.76 | .65 | .27 | .68 |
8–23–43 | 13 | .28 | 1.78 | .63 | .26 | .69 |
| 14 | .29 | 1.85 | .65 | .27 | .68 |
Table VI
Reproducibility tests, Nitralloy G steel.
Type and date of analysis | Test No. | Mo % | Al % | Cr % | Si % | Mn % |
---|
Wet analysis | 1 | 0.18 | 0.96 | 1.13 | 0.19 | 0.48 |
Spect. analysis |
8–17–43 | 1 | .18 | 0.99 | 1.14 | .19 | .48 |
| 2 | .18 | 0.94 | 1.10 | .19 | .49 |
8–18–43 | 3 | .17 | 0.94 | 1.12 | .18 | .48 |
| 4 | .17 | 0.97 | 1.11 | .18 | .48 |
8–19–43 | 5 | .17 | 0.98 | 1.13 | .19 | .47 |
| 6 | .18 | 0.97 | 1.16 | .19 | .48 |
8–20–43 | 7 | .19 | 0.93 | 1.10 | .19 | .48 |
| 8 | .19 | 1.00 | 1.14 | .20 | .50 |
8–21–43 | 9 | .18 | 0.96 | 1.13 | .19 | .48 |
8–25–43 | 10 | .19 | 0.95 | 1.14 | .20 | .51 |
| 11 | .19 | 0.94 | 1.13 | .20 | .50 |
Table VII
Reproducibility tests on grey iron.
Type of analysis | Test No. | Silicon % | Manganese % |
---|
Wet analysis | 1 | 1.95 | 0.61 |
Spect. analysis | 1 | 1.95 | .59 |
| 2 | 2.00 | .59 |
| 3 | 1.97 | .58 |
| 4 | 1.92 | .62 |
| 5 | 2.00 | .62 |
| 6 | 1.93 | .61 |
| 7 | 2.02 | .62 |
| 8 | 1.93 | .59 |
| 9 | 1.95 | .61 |
| 10 | 1.95 | .62 |
| 11 | 2.00 | .60 |
Wet analysis | 2 | 2.45 | .63 |
Spect. analysis | 1 | 2.42 | .63 |
| 2 | 2.47 | .65 |
| 3 | 2.42 | .63 |
| 4 | 2.50 | .64 |
| 5 | 2.40 | .63 |
| 6 | 2.46 | .63 |
| 7 | 2.40 | .65 |