Moderator KBK Pengelasan – Farid M. Zamil sering berbagi informasi mengenai pengelasan dan pengetahuan bahan. Kali ini sharing beliau mengenai “Effect of The Individual Alloying Element on The Material Properties” (dokumen terlampir).

EFFECT of THE INDIVIDUAL ALLOYING ELEMENT ON THE
MATERIAL PROPERTIES

By : Farid Moch. Zamil

1. Constant Fe – Alloying elements : C ; Si ; Mn..

(a). Carbon ( C ) 0 – 1.5 % (2.3 %)

Most important alloying element, strongly increasing the tensile strength and
wear resistance; decisive for hardenability and maximum hardness of tool
steels.

Content for different steel grades :

0.01 – 0.10 % Steels with good forming capabilities, such as deep drawing
steels ; corrosion resistant ; not magnetising steels ; steels for
case hardening.

0.15 – 0.35 % General contruction steels with good tensile properties such
as elevated contruction steel, free machining steel.

0.40 – 0.80 % High tensile construction and tool steel such as heat treateble
steels, hot work steels, spring steels.

0.80 – 1.40 % Tool steels, wear resistance steels.

1.40 – 2.10 % Highly – Stressed cold work steels, high speed steels.

(b). Silicon ( Si ) 0.20 – 1.6 % (14 %) (Alloying Element)

Alloying and De – oxidation element (NMI – Si – Oxide), strongly increases
tensile properties, high elaticity limit (spring steels) ; Above 2 % Si only a
more limited elongation. Over 4 % practically unformable, increase in wear
resistance. Hardness scaling and corrosion resistance ; Above 10% Si (only
castable ) acid resistant ; for magnets, soft parts (dynamo and transformer
sheets) ; Si promotes graphite formation from cementite. Si is the primary
alloying element after C in grey cast iron.