Cause of Cracks after Heat Treatment Precision Steel Tubes

Factors of alloy tube heat treatment cracks may include the following:
1, Forging burnt
2, Large pieces of non-metallic inclusions
3, In the bar before forging frequency heating, bar table in relatively large temperature difference (may be cracking phenomenon in the vehicle processing).
4, The original tissue severe heat treatment failure
5, The heat treatment temperature is too time limit (temperature furnace run, reach more than 900 degrees, quenching dropped out on the break).
6, There is no time after quenching and tempering (generally best not more than 1 hour)
7, product dimensions question