But the melting point of zinc is about 420 a nd it ' s vaporating point is 906 但锌的熔点约为420 ,挥发温度为906 ,不利于焊接。
2.
B2o3 could barrier the diffusion of o2 and na2so4 steam into interphase downwards of 1273k of volatilization temperature of b2o3 氧化硼在其挥发温度( 1273k )以下能够有效阻挡氧及部分硫酸钠蒸汽的进一步扩散,从而保护了纤维。