18CrNiMo7-6 is a case hardening steel with high toughness. There are a number of variants with high cleanliness requirements. All variants possess tighter composition ranges compared to the standard. One variant is produced with the quality class IQ (isotropic quality). This ensures a very low number of elongated sulphide inclusions which will give more isotropic properties. The high oxidic cleanliness will enable the steel to meet the same high cleanliness demands as for re-melted qualities.
Grade 159A - Variant with low sulphur content and high cleanliness demands
Grade 159B - Variant with controlled sulphur content for consistent machinability and +H hardenability
Grade 159Q - Isotropic properties (IQ) and better fatigue strength due to higher cleanliness levels, and a finer size and distribution of non-metallic inclusions
Grade 159X - Variant with controlled sulphur content for consistent machinability and +H hardenability
Grade 159S - Variant with increased sulphur content.
Grade 4761(MoCN216) - Low sulphur variant of Imatra
IQ-Steel® is an isotropic quality ultra clean steel optimized for high fatigue strength under multi axial loading.
For additional Heat Treatment Data, please visit the Heat Treatment Guide.
1.6587, AISI4820, DIN17CrNiMo6, 18CND6, EN ISO 683-17