<p>The network structure of M₂B in Fe-B-C alloy readily leads to the failure of material. In this work, by adding K₂SO₄, the morphology of the M₂B was successfully regulated through a synergistic treatment combining active element modification and heterogeneous nucleation modification. The results show that after the addition of K₂SO₄, a new phase α-MnS forms in the alloy, and the active element K enriches at the M₂B/matrix interface. This inhibits the growth of the network M₂B and promotes its transformation from a continuous network structure to an isolated blocky structure. As the K₂SO₄ addition increases from 0wt.% to 4.46wt.%, the shape factor value of M₂B increases from 0.067 to 0.353, with an increase of 426%. The impact toughness of the alloy increases from 5.9 J·cm⁻² to 14.2 J·cm⁻², and the fracture mode transitions from cleavage fracture to ductile-cleavage mixed fracture. Three-body abrasion tests indicate that with increasing K₂SO₄ addition, the wear weight loss of the alloy gradually decreases. The alloy with 4.46wt.% K₂SO₄ addition exhibits the least wear damage and the best wear resistance. This work provides an effective approach for regulating the microstructure and improving the wear resistance of wear-resistant Fe-B-C alloys.</p>