The thermal conductivity of steel wire rod typically varies with different grades. Higher-grade steel wire rod tends to have a higher thermal conductivity compared to lower-grade steel wire rod. This is because higher-grade steel wire rod is usually made with superior quality materials and has a more refined structure, allowing for better heat transfer. However, it is important to note that the exact variation in thermal conductivity can depend on various factors such as alloy composition, heat treatment, and processing techniques used during the manufacturing process.