The precipitationPrecipitation of BN during the cooling processProcess of boron containing steelBoron containing steel continuous castingContinuous casting not only reduces the effective boronEffective boron content in the steelSteel and weakens the beneficial effect of boronBoron alloying, but also increases the sensitivity of the cast billet to cracksCrack. The competitive precipitation behaviorCompetitive precipitation behavior between BN and TiN was studied through thermodynamicThermodynamic calculations, and the influence of Ti and N content in steelSteel on BN precipitationPrecipitation behavior was investigated. The research results indicate that as the Ti content in steelSteel increases, the precipitationPrecipitation of BN is gradually inhibited. The formula for calculating the critical amount of titanium addedCritical amount of titanium added to completely suppress BN precipitationPrecipitation is wTi(No BN) = (3.3wN + 3.22)wB + 3.36wN. The critical titanium addition amount wTi(No BN) increases with the increase of N and B content in steelSteel. The research results provide important theoretical basis for the composition design of boron containing steelBoron containing steel and the quality control of continuous castingContinuous casting billets.