Prakt. Met. Sonderband 38 (2006) 389 
distence of Optical metallography was performed on samples in various sequences of experimental 
castability, works. For this purpose the samples grinded using emery papers up to 3000 grit (EU 
standard), then polished with 1 ym diamond paste and finally etched with various etchants. 
nitic in the Several etchants were used, but since the corrosion resistance of the Sandvik steel is very 
hermal or high only some of them were able to affect on samples. Those strong etchants are shown 
in table 2. 
se steels At last samples were subjected to thermal etching in air up to 300 °C but no considerable 
/ different results achieved. It seems that this type of steel has highly anticorrosive properties up to 
TAP®[1-4], this temperature. 
able about 
ir optical Table 1: Chemical composition of samples, Wt% 
ms logical mn _ _ 
of optical Sample Code | Cr | Ni [Mo | V | Cu | Ti C |Rem 
alectrolyte 1 9191279 2717 [0002| Fe_ 
f Sandvik 2 10 
ques and 3 10 
it 0010 08 1 2) 1 
ace of the I one 20 212 0/02 | Fe 
ast at the A ey OB IB 2' 1 [0/02] Fe 
as grain ile | 10 a 2 | + 1002 
Whe (12797 4 2 1'a Jo/02] Fe 
entage of i 2191411 2) 7 [G02] Fe 
prevents 10 1619] 41112 0/02 | Fe 
within the 11 11:14 T1121 7 [02] Fe 
ss Steels =u 10 0/02 | Fe 
13 110740. 4 | --1 211 [002[ Fe 
f steel by a ET 
eduction, 
th higher Table 2: etchants and techniques used in this research 
> surface 
erable to ___ _Etchant Technique Etchant Composition 
locations ____Aquaregia Soaking 45 ml Hydrochloric Acid, 15 ml Nitric Acid 
ng; Fry Soaking 5 g Copper Chloride, 40 ml Hydrochloric 
Acid,25 ml Ethanol, 30 ml Water 
Glyceregia Soaking 30 ml Glycerol, 50 ml Hydrochloric Acid, 
_ 10 ml Nitric Acid 
Kalling Soaking 5 g Copper Chloride, 100 ml Hydrochloric 
urnace is a Acid, 100 ml Ethanol 
)*30 mm. Nitric Acid Electrolytic 60 ml Nitric Acid, 40 ml Water 
that their Orthophosphoric Acid Electrolytic _ 10% Orthophosphoric acid in methanol 
) °C for 1 Hydrochloric Acid Electrolytic, 5 ml Hydrochloric Acid, 95 ml Methanol 
>. Finally, V2A Hot 10 ml Nitric Acid, 100 ml Hydrochloric Acid, 
amounts Soaking 100 ml Water, (50 °C) 
» in order 
3. Results and Discussion 
Recommended etching time when various etchants were used for as cast bars is shown in 
table 3. Etching time for Orthophosphoric acid did not consider in this research. Table 4 
shows the suitable voltage for electrolytic etching.