ASTM A278 class 35C
is a grade of carbon steel and low alloy steel castings that has a minimum
tensile strength of 35,000 psi (240 MPa), a minimum yield strength of
22,000 psi (150 MPa), and a minimum elongation of 22%. This grade of cast steel
is commonly used in general-purpose applications that require good strength and
toughness, as well as resistance to wear and corrosion.
In ASTM A278, the letter
"C" following the numerical value, such as "35C", indicates
that the material is a carbon steel casting. The "C"
designation is used to distinguish carbon steel castings from other types of
castings, such as alloy steel or stainless-steel castings, which may have
different chemical compositions and mechanical properties.
In the case of ASTM A278
class 35C, the material is a carbon steel and low alloy steel casting with a
minimum tensile strength of 35,000 psi, a minimum yield strength of 22,000 psi,
and a minimum elongation of 22%. The specific chemical composition of the
material includes carbon, manganese, silicon, phosphorus, sulfur, and potentially
other trace elements.
Note:
It is important to note
that ASTM A278 class 35C is a grade of carbon steel and low alloy steel
castings, not gray iron. Gray iron is a different type of cast iron that is
characterized by its gray color, which is due to the presence of graphite flakes
in the microstructure.
ASTM A278 does include
several grades of gray iron castings, including classes 30, 35, and 40. These
grades of gray iron have different mechanical properties and are used in a
variety of applications, such as engine blocks, gears, and machine tool bases.
Compared to gray iron,
steel castings such as ASTM A278 class 35C typically have higher strength and
toughness, as well as better resistance to wear and corrosion. The specific
choice of material will depend on the specific requirements of the application,
including the operating conditions, the design of the component, and the
required properties of the material.
Equivalent grades
There are several
equivalent grades to ASTM A278 class 35C, which may vary depending on the
country or region. Some of the equivalent grades are:
- BS3100 grade A4
- DIN 1681 grade GS45
- EN 10293 grade G35
Chemical composition
The chemical composition
of ASTM A278 class 35C castings typically includes:
- Carbon (C): 0.25% max
- Manganese (Mn): 0.70-1.00%
- Silicon (Si): 0.15-0.50%
- Phosphorus (P): 0.035% max
- Sulfur (S): 0.040% max
Additionally, this grade
of cast steel may also contain trace amounts of other elements, such as copper
(Cu), nickel (Ni), and chromium (Cr), depending on the specific composition and
intended application.
The properties of ASTM
A278 class 35C castings are determined by a combination of its chemical
composition, microstructure, and processing conditions. Generally, this grade
of cast steel exhibits good strength, toughness, and wear resistance, as well
as good machinability and weldability. However, the exact properties of the
material can vary depending on the specific casting process and heat treatment
used, as well as the quality of the casting itself.
Mechanical properties
The mechanical
properties of ASTM A278 class 35C castings are specified in the ASTM A278
standard. The typical mechanical properties of this grade of cast steel are:
- Tensile strength: minimum 35,000 psi
(240 MPa)
- Yield strength: minimum 22,000 psi
(150 MPa)
- Elongation: minimum 22%
- Hardness: maximum 217 Brinell (HB)
It is important to note
that the actual mechanical properties of the casting may vary depending on
factors such as the casting process, section size, cooling rate, and heat
treatment. The mechanical properties of the casting can be tested and verified
through various methods such as tensile testing, impact testing, and hardness
testing. The specific mechanical properties required for a particular
application will depend on the operating conditions and the design requirements
of the component.
Applications
ASTM A278 class 35C
castings are commonly used in a variety of general-purpose applications
that require good strength, toughness, and resistance to wear and corrosion.
Some of the typical applications of this grade of cast steel include:
- Valves: ASTM A278 class 35C castings
are commonly used in the manufacturing of valve bodies, stems, and other
components that require good mechanical properties and resistance to wear
and corrosion.
- Fittings: This grade of cast steel is
also used in the manufacturing of fittings such as pipe elbows, tees, and
reducers, which are used in various piping systems.
- Flanges: ASTM A278 class 35C castings
are often used in the manufacturing of flanges, which are used to connect
piping systems and other equipment.
- Pump, and compressor components: This grade of cast
steel is also used in the manufacturing of casings, impellers, and
other components that require good strength and resistance to wear and
corrosion.
- Mining equipment: ASTM A278 class 35C
castings are commonly used in the manufacturing of various mining
equipment such as dragline buckets, excavator buckets, and crusher liners.
Overall, ASTM A278 class
35C castings are widely used in various industrial applications that require
good mechanical properties and resistance to wear and corrosion. The specific
application of this grade of cast steel will depend on a variety of factors,
including the operating conditions, the design of the component, and the
required properties of the material.
