Welding Carbon and Alloy Steels 2nd Year
What is the carbon content range of low carbon steels?
0.05% to 0.30%
What is the carbon content range of medium carbon steel?
0.30% to 0.45%
What is the carbon content range of high carbon steels?
0.45% to 0.75%
What is the carbon content range of very high carbon steels?
0.75% to 1.50%
Which governing body writes specifications for structural steel shapes and plates?
ASTM
Which two organizations work closely together in issuing steel specifications for the fabrication of boilers and pressure vessels?
ASTM and ASME
If a SMAW alloy electrode contains nickel as the major alloy addition in the coating, which letter would be in the suffix?
C
The slag of an E10018 is similar to the slag of which electrode?
E7018
Which steels are designed to provide improved strength, corrosion resistance or notch toughness while retaining good weldability?
HSLA
What is one characteristic of high strength low alloy steels?
They have a higher strength-to-weight ratio than carbon steels.
How are the mechanical properties of low alloy SMAW electrodes improved over low carbon electrodes?
by adding alloying elements to the coating
What is the principal hardening agent in steel?
carbon
In the SAE or AISI number 1025, the number 25 indicates the:
carbon content in hundredths of 1%.
What is indicated by the first digit in the SAE or AISI numbering system?
class of steel
Leaf springs used on automobiles are made from what type of carbon steel?
high carbon steel
What is one advantage of using low alloy steels?
improve resistance to heat and corrosion
What is the purpose of having a chromium content of 10% to 30% in steel?
increase corrosion resistance
What is the major ingredient in the coating of an E9018?
lime
What type of material is E8018-B2L suitable for?
low alloy steels containing 0.50% to 1.25% chromium, 0.50% molybdenum
Which class of steel is generally tough, ductile, easily formed and usually welded without preheat?
low carbon
Structural shapes are made from what type of carbon steel?
low carbon steel
Which element in carbon steels, in percentages up to about 0.80%, is intended to combine with sulphur to offset embrittlement and hot shortness?
manganese
Which element, in percentages of 1% to 15%, increases the toughness and hardenability of steel?
manganese
Axles and connecting rods are made from what type of carbon steel?
medium carbon steel
The suffix A1 indicates what specific alloy has been added to the coating?
molybdenum
Which element is used to decrease high temperature creep (slow stretching of steel under stress at high temperatures)?
molybdenum
Which element increases the strength and toughness of steel at low temperatures?
nickel
In high percentages, this element is considered an impurity. In low percentages up to approximately 0.01%, it slightly improves the strength and corrosion resistance of low carbon steel.
phosphorus
The SAE and AISI use the same numbering system for what type(s) of steel products?
steel bars
The content of this element in carbon steel is usually kept below 0.05%, but a content of 0.1% to 0.15% can improve its machinability.
sulphur
Which two elements exist in small quantities in carbon steels and are usually considered impurities?
sulphur, phosphorus
What do the suffixes such as A1, B4 or C3 refer to in low alloy electrodes?
the specific additions of alloying elements
In the AWS classification system for low alloy electrodes, what identifies the specific additions for alloys?
the suffixes
Why are small amounts of nickel, chromium or molybdenum added to low alloy steels?
to increase strength, hardness and toughness
Why is tungsten alloyed with tool steels?
to retain hardness at high temperatures
Why is preheat necessary in the welding of most high carbon steels?
to slow down the cooling rate
What is the alloying element in carbon steel that tends to produce a fine grain structure during the heat-treating process?
vanadium
Punches and dies are made from what class of carbon steel?
very high
