Gray Iron Material Grades Choosing Guide

This guide will help gray iron casting purchasers to learn how to choose suitable gray iron material grades for their casting products.

1. What gray iron grades you could choose?

The following table is showing all the gray iron material grades for each country. So, if you are American, then you could choose No.20, No.30, No35, or No45 etc., if you are from Australia, then you could choose T150, T220, T260 or T300 etc.

2. What is the function of material grades?

The material grades are from their specific material standards, for example, in USA, the common material standard for ductile iron is ASTM A48, in this standard, you could find the mechanical properties for No.25 tensile strength min. 172 Mpa, No.30 tensile strength 207 Mpa.

Therefore, when you tell us what material grades you need, then we will know what mechanical properties you required, then we could produce your casting parts accordingly.

3. How to choose the suitable gray iron grades?

Choosing the gray iron material grades is a very professional work, normally, only the professional material engineer could choose the suitable grade, but if you are not a material engineer, but you have to make one choice, then the following methods may help you.

A. Please check the 2D drawings, and the technical requirements you have, then you may find some clue for "material", the completed drawings should denote the material grades.

B. If you can not find any material information from drawings, then you may need to consider it by your experience. The following experience will help you.

B1. If you just need it to be gray iron or cast iron, and do not have special requirement to its mechanical properties, then you could choose "No.20 or No.25" (equal grades for other countries will be GG15, EN-GJL-150, T150, Grade 150, HT150). The above material equivalent table will help you.

B2. If you need the material have high strength, strong enough, could take comparatively high load force, then you could choose "No. 30" or higher grade "No.35" (for its equal grades, please refer to the above material grade table).

B3. If you need the material have very high strength, need to take very high pressure load, need it to be very strong, then you could "No.40 " or "No.45".

Let me to explain more about this point. For some products, such as stove parts, the high material grades will cause some difficulties to further drilling works, so do not require high grades for these parts, higher grades will cause some higher production costs, and higher defective rates, so unless you really need, otherwise, the lower grades will be better for casting production.

4. Some important issues for choosing gray iron material grades

For most of Chinese foundries, we could produce the low and middle gray iron material grades, but not everyone could produce high gray iron grades, such as No.50, or No.60, they will need further heat treatment, so if you need very high tensile strength, but do not need the special mechanical properties of gray iron, you could consider the ductile iron materials, which will be stronger and tougher than gray iron.

If you still can not make a good choice, then you could get help from some material engineer, or just tell your requirements to us. You just need to tell us where your parts will be used, and what is your application requirements, then, we will give you our suggestion.

Home Page  |  Casting Products  |  Contact Us