- Carbon will cause a very bright and feathery spark just as one might see on a child’s sparkler. The more carbon present in the steel, the brighter and more plentiful are the bursts.
- Molybdenum will tend to diminish the sparks on the feathery bursts and will give off a yellow color. In the stainless steels, the chromium produces a much-diminished spark. In the tool-steel range, the molybdenum will produce a long-stream spark, which emerges almost as a spear point would be at the tip of the spark.
- Chromium will produce an orange spark. In the stainless steels, the chromium produces a much-diminished spark. In the tool-steel range, chromium will tend to make the spark long with small spark streams coming off the main spark.
- Tungsten will suppress the spark color to a darker orange to red color and also suppress the ability for the steel to make a spark, particularly with high-tungsten steels.
- Nickel will tend to make the spark long and clear until at the end of the spark stream when there is a slight burst.
- Manganese will brighten the spark and tends to make the spark go around the grinding wheel.
Spark Testing: Seeing the Spark
During the last blog, the preparation of the sample was discussed. It can be seen that while the test is not a quantitative test or a conclusive test, it is at least an indicative test of identification. What effect do the alloying elements have on the resulting spark of the sample?