ASTM Epdf – Download as PDF File .pdf), Text File .txt) or read online. ASTM E Standard Practice for Microetching Metals and Alloys. Basic Description: ASTM E is a method of etching a metal sample to reveal its microstructure. On a microscopic scale, metal is made up of many grains which.
Solution composes on standing. Excellent grain boundary etch for ferritic stainless steels. If dried particles are noted on or near the lid, submerge the bottle in water to re-hydrate them before opening. Continued Uses general structure grain boundaries general structure etch-polishing for viewing grains with polarized light Etchants66,,a a Osmium Base: Multiple etching may be required. Staining and pitting increase as CrO3 increased.
ASTM E – 07()e1 Standard Practice for Microetching Metals and Alloys
Use carbon cathode raising d-c voltage from 0—30 V in 30 s. Pure Co Hard-facing and tool metals High-temperature alloys 9, 10 11 12, 13c general structure via polarized light general structure general structure 14, 15, 16, 17 18, 19, 20 20, 18, 16, 21, 22b, 24, 25 19 general structure general structure general structure phase identi?
Immerse 1—2 s at a time and immediately rinse with methanol. Add nitric acid to lower the pH to 2. John Wiley and Sons. Additionally, one can contact the glove manufacturer or, if available, consult the manufacturers glove chart.
All persons using any etchants should be thoroughly familiar with all of the chemicals involved and the proper procedure for handling, mixing, and disposing of each chemical, as well as any combinations of those chemicals. Pure Mg, 74a,74a,74a,,, 74a,,, 74a, 1d,,, 74a, 1d,, 98c, a general structure stain-free polish-etch general structure general structure phase identi?
Properly discard Solution B after 1 hr. Immerse 30 s—3 min. Swab or immerse few seconds to a minute.
Good microstructural results require significant preparation to obtain a mirror finish with no scratches or edge rounding prior to etching. Electrolytic at 30—65 V for 10—60 s. Space electrodes 2 cm apart. Precision and Bias 8. A selection of useful books on this subject is given in Refs. Etch time varies with material. Electrolytic at 6 V for few seconds to a minute.
Solution should be freshly prepared. For more corrosion resistant alloys.
Immerse or swab 5 to 30 s. Do not store Properly discard after use. Rinse in Solution B. Adding a wetting agent such as zepherin chloride will increase response.
After polishing, the surface must be carefully cleaned. Care sstm be taken to keep it moist because dry picric acid is shock sensitive and highly explosive especially when it is combined with metals such as copper, lead, zinc, and iron. As cast Nickel Base: Must be used e4407. Polishes at high currents. Pure Th Th alloys Tin Base: Electrolytic at 5 V ac for 1—2 min. Total etching time 3 min 50 mL Carbitol diethylene glycol monoethyl with agitation. Repeat three times and repolish lightly.
Tends to pit with longer times. Will not attack sul? Stains sigma and chi yellow to red brown, ferrite gray to blue gray, carbides barely touched, austenite not touched.
Standard Practice for Microetching Metals and Alloys
Electrolytic at 50—60 V for 10—20 s. It may be helpful to place the specimen on a small piece of white paper. Etching rate is increased, sensitivity decreased with increased percentage of HNO3. Immerse to 2 min to darken matrix to reveal carbides and phosphides. Properly discard when dark orange aetm. Add the HCl just before using. May be used electrolytically.
Can be heated to increase activity. Works best with attack-polished specimens.