BS EN ISO 439:2020

What is ISO 439 about ? 

ISO 439 is an international standard on steel and cast iron to determine the silicon content in steel and cast iron. 

ISO 439 specifies a gravimetric method for the determination of the silicon content in steel and cast iron. 

ISO 439 is applicable to silicon contents between 0,10 % (mass fraction) and 5,0 % {mass fraction). 

ISO 439 provides you gravimetric method for testing silicon content which includes acid dissolution of the test portion and formation of hydrated silicon dioxide, filtration and washing, recovery of silicon compounds in the filtrate and ignition of silicon dioxide. 

Note: In ISO 439, for samples containing molybdenum, niobium, tantalum, titanium, tungsten, zirconium or high levels of chromium, the results are less accurate than for unalloyed matrixes. 

Who is ISO 439 for ? 

ISO 439 on steel and cast iron is applicable to: 

• Manufacturers of steel and cast-iron components 
• Dealers and importers of steel and cast-iron components 
• Raw material suppliers of steel and cast-iron applications 

Why should you use ISO 439 ? 

Silicon acts as a graphite stabilizing element in cast iron. In steel, silicon is used to reduce grain resistance, increasing strength and hardness, however, it can also be detrimental to surface quality.  

ISO 439 provides you with information on principle, reagents, apparatus, sampling, procedure, expression of results and test report which allows you to enhance the quality of steel and cast-iron components. 

The methods and procedures provided by ISO 439 helps you to improve corrosion resistance of steel and cast-iron components. 

What’s changed since the last update ? 

BS EN ISO 439:2020 supersedes BS EN ISO 439:2010, which is now withdrawn. 

The main change in BS EN ISO 439:2020 includes - a complete re-evaluation of the precision data.