Rock drill insert

A rock drill insert comprising:

• a body of cemented carbide including hard constituents of WC in a binder phase including cobalt, wherein the cemented carbide includes 4-18 wt % Co, Cr such that a Cr/Co mass ratio in an innermost part of the rock drill insert is 0.04-0.19, and a balance of WC and any unavoidable impurities,
• wherein content of the binder phase of the cemented carbide is substantially equal throughout the rock drill insert;
• a hardness of at least 800 HV20, wherein hardness is measured according to EN ISO 6507-1:2005 (E),
• wherein a WC grain size mean value of the cemented carbide is above 0.7 μm but less than 18 μm as measured according to Jeffries method
• wherein
• said insert has a corrected CoM/wt % Co ratio between 0.70-0.81 and is substantially free of eta-phase, wherein eta-phase is M6C or M12C where M=(Co, W, Cr), and
• wherein said corrected CoM/wt % Co ratio is calculated according to:
• Corrected
• ⁢
• CoM
• /
• wt
• ⁢
• %
• ⁢
• Co
• =
• (
• magnetic
• -
• %
• ⁢
• Co
• +
• 1.13
• *
• wt
• ⁢
• %
• ⁢
• Cr
• )
• /
• wt
• ⁢
• %
• ⁢
• Co
• where magnetic-% Co is a weight percentage of magnetic Co and wt-% Co and wt-% Cr are a weight percentage of Co and Cr in the cemented carbide, respectively.