MA Plasthard

Screw and cylinder material with super corrosion/wear resistance.
MA Plasthard S (Round bar for screws)
MA Plasthard B-2 (Material for cylinders and screws)

Aerospace & Energy Materials Dept.

Main Features

For many years Proterial, Ltd. Okegawa Works has manufactured and sold MA Alloy, which is a super corrosion-resistant alloy, and BISHILITE (Hard-Facing Alloys), which is a wear-resistant alloy. MA Plasthard is an alloy that has the combined advantages of a super corrosion-resistant alloy and a wear-resistant alloy, and it is used for cylinders and screws of various plastics or rubber extrusion machines and injection molding equipments. Our Plasthard alloys can serve to bring higher efficiency and stable operation to extrusion machines and injection molding equipments.

Mechanical properties

Advantages of high strength

This alloy is produced by forging. The cylinder material (MA Plasthard B-2) and screw material (MA Plasthard S & B-2) both have strength 1.5~1.8 times higher than chromium Molybdenum steel (thermal refined), and moreover, it maintains 7~20% elasticity, enabling rigorous design. The alloy will not chip since it is fully resistant to thermal and mechanical shocks. Since welding is also possible, stains can be prevented completely as shown in the "Example of installation" figure.

  Tensile
strength
(N/mm2)
Yield
strength
(N/mm2)
Elongation
(%)
Coefficient
of Thermal
Expansion
(°C)
Specific
thermal
conductivity
(W/m,K)
Torsional
Strength
(N/mm2)
Impact
strength(J)
CharpyV)
Plasthard S 1363 1098 26 12.4X10-6 9.4 834 127
Plasthard
B-2
1237 782 25 11.5X10-6 11.3 981 58
Example of the installation of the MA Plasthard B-2 liner by the insertion method.

Mechanical properties in high temperatures(MA Plasthard S)

Cutting and Grinding conditions

For cutting & grinding processes, use materials such as Mitsubishi Materials' DIATITANIT HTi10 (JISK10) or HTi05T (JISK01). In particular, U615 (coated) shows excellent performance in grinding.

Available Product Forms

Bars and forgings can be manufactured.

Corrosion Resistance

Corrosion Resistance

  Plasthard S Plasthard B-2 Nitrided steel Ni-Co-Cr-B
50%Hydrochloric acid
(*36% Hydrochloric acid)
0.05mm/Year 0.08mm/Year* 13mm/Year 0.4mm/Year
50% Sulfuric acid 0.003mm/Year 0.05mm/Year 3mm/Year 0.2mm/Year
10% Hydrofluoric acid
10% Hydrochloric acid
0.15mm/Year 0.46mm/Year 6mm/Year 0.2mm/Year

Hardness

  Plasthard S Plasthard B-2 Ni-Co-Cr-B Ni-Cr-Mo Bishilite No.12
Rockwell C hardness 40~45 25~35 41~48 (18) 47
(Converted to Shore hardness) 53~59 38~49 54~64 30 63
Bishilite : Hard-Facing Alloys.