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采用XRD,OM,BSE,SEM和显微硬度计等手段研究了氘含量对Zr-4合金显微组织及力学性能的影响.结果表明,随着氘含量(质量分数)从1.35%增加到2.21%,氘化物数量增加,其形态及分布也发生了显著变化:在1.35%时,主要以晶内针状氘化物析出为主;随着氘含量增加,晶界块状氘化物快速增长;当氘含量进一步增加至2.21%时,晶界块状氘化物开始相互衔接,并逐渐向晶内生长.在氘含量较高的样品表层,有一定厚度的氘化物层形成,且层内出现微裂纹.所形成的氘化物以d-氘化物为主,而高氘含量样品表面有e-氘化物出现.样品心部至表面存在一定的硬度梯度,且随着氘含量的增加,样品的硬度增加,其相应的硬度梯度增大.随氘含量增加,样品的屈服强度略有增加,而抗压强度却显著下降,由1.35%下的1176 MPa降低到了2.21%下的856 MPa.抗压强度的降低与组织中微裂纹有关.样品压缩后的裂纹主要沿晶界块状氘化物形成并扩展,因此晶界块状氘化物是材料压缩性能下降的主要原因.
The effects of deuterium content on the microstructure and mechanical properties of Zr-4 alloy were studied by means of XRD, OM, BSE, SEM and microhardness tester.The results showed that with the increase of deuterium content (mass fraction) from 1.35% to 2.21 %, The number of deuterated compounds increased, and their morphology and distribution also changed significantly. At 1.35%, the intragranular acicular deuterated compounds mainly precipitated. With the increase of deuterium content, the intergranular deuterated compounds increased rapidly. When When the deuterium content further increases to 2.21%, the intergranular dendrimers begin to inter-connect with each other and gradually grow into the intergranular.When deuteride layer with a certain thickness is formed on the surface of the sample with high deuterium content, The deuteride formed was mainly d-deuteride, while the e-deuteride appeared on the surface of the sample with high deuterium content.The hardness of the sample increased with the increase of deuterium content , The corresponding hardness gradient increases.With the increase of deuterium content, the yield strength of the sample increases slightly, but the compressive strength decreases significantly from 1176 MPa at 1.35% to 856 MPa at 2.21% .Compressive strength Decrease is related to the micro-cracks in the microstructure Deuteride bulk form and expand, thus the grain boundary is the main bulk deuteride compressive performance degradation.