等离子喷涂结晶器用ZrO_2-MoSi_2复合涂层的组织及抗热震性能

Structure and Thermal Shock Resistance of ZrO_2-MoSi_2 Composite Coating for Mould Prepared by Plasma Spraying

为了优化连铸结晶器铜板的性能并延长其使用寿命,采用自制Zr O2-Mo Si2团聚型复合粉末通过超音速大气等离子喷涂技术在结晶器Cr Zr Cu铜板表面制备了Zr O2-Mo Si2/Co Ni Cr Al Y复合涂层。利用SEM、XRD等观察涂层的微观形貌并分析其物相组成,通过拉伸试验测定涂层与基体的结合强度,通过抗热震试验测定涂层的抗热震性能。结果表明:复合涂层表面熔化良好且致密,其与Cr Zr Cu铜板基体具有良好的结合性能,平均结合强度为32.210 MPa;复合涂层分别在500,600,700℃下保温后通过水淬法测试其抗热震性能,结果涂层从裂纹产生至涂层失效分别经历了131.3,66.3,34.0次(子弹型试样),147.3,65.7,48.3次(硬币型试样)。

In order to optimize the performance of continuous casting mould copper plate and prolong its lifetime,the ZrO_2-MoSi_2 CoNiCrAlY composite coatings were prepared on CrZrCu mould copper plate by using ZrO_2-MoSi_2 agglomerated compound powder through supersonic speed air plasma spraying.The SEM and XRD were used for observing the microstructure and analyzing the phase composition of the coatings.Results showed that the composite coating melted well and had dense surface,and the average adhesive strength was32.210 MPa,which indicated that the coating had excellent adhesive strength with the CrZrCu copper substrate.In addition,the thermal shock resistance of the compound coatings was tested at 500,600,700℃ by water quenching method,and the test results presented that the coating from cracks to failure went through131.3 times,66.3 times and 34.0 times for bullet-type specimens,or 147.3 times,65.7 times and 48.3 times for coin-type specimen,respectively.