Abstract The thin-walled structures of Al2O3-ZrO2 ceramic were deposited using laser direct material deposition (LDMD). The effect of heat input on Al2O3-ZrO2 ceramics with different Al2O3/ZrO2 powder weight ratios were studied and the microstructures in different regions of the deposit were analyzed. For the thin-walled structure with 85 wt% Al2O3 and 15 wt% ZrO2 (H1) hypoeutectic deposition, the grain growth angle increases with increasing heat input. From the frontier region to the central region, the microstructure was transformed from a columnar dendritic structure to a cellular structure. For thin-walled structure with 65 wt% Al2O3 and 35 wt% ZrO2 (H2) hypoeutectic deposition, the mean thickness of the banded structure increases with increasing heat input but decreased when the heat input was 124.3 J/mm. The minimum thickness of the banded structure was 0.16 mm. The microstructure of the frontier region exhibited cellular dendritic, while the amorphous structures appeared in the central region. The maximum hardness of the thin-walled structure with H1 hypoeutectic deposit was 21.4 GPa while the maximum fracture toughness of the H2 hypoeutectic deposit was 4.61 MPa m1/2. The fracture toughness was found to increases as the thickness of the banded structure decreases under high heat input. The results of this research provide some basis for attaining high quality Al2O3-ZrO2 ceramics by laser direct material deposition.

中文翻译：

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激光直接材料沉积法沉积Al 2 O 3 -ZrO 2 陶瓷的组织和力学性能

摘要 采用激光直接材料沉积（LDMD）方法沉积了Al2O3-ZrO2陶瓷的薄壁结构。研究了热输入对不同Al2O3/ZrO2粉末重量比的Al2O3-ZrO2陶瓷的影响，并分析了沉积物不同区域的微观结构。对于具有 85 wt% Al2O3 和 15 wt% ZrO2 (H1) 亚共晶沉积的薄壁结构，晶粒长大角随着热输入的增加而增加。从前沿区域到中心区域，微观结构由柱状树枝状结构转变为蜂窝状结构。对于具有 65 wt% Al2O3 和 35 wt% ZrO2 (H2) 亚共晶沉积的薄壁结构，带状结构的平均厚度随着热输入的增加而增加，但在热输入为 124.3 J/mm 时减小。带状结构的最小厚度为 0.16 毫米。前沿区域的微观结构呈现出蜂窝状树枝状结构，而中心区域则出现非晶结构。H1亚共晶沉积薄壁组织的最大硬度为21.4 GPa，H2亚共晶沉积的最大断裂韧度为4.61 MPa m1/2。发现在高热输入下，随着带状结构的厚度减小，断裂韧性增加。该研究结果为通过激光直接材料沉积获得高质量的 Al2O3-ZrO2 陶瓷提供了一些基础。H1亚共晶沉积薄壁组织的最大硬度为21.4 GPa，H2亚共晶沉积的最大断裂韧度为4.61 MPa m1/2。发现在高热输入下，随着带状结构的厚度减小，断裂韧性增加。该研究结果为通过激光直接材料沉积获得高质量的 Al2O3-ZrO2 陶瓷提供了一些基础。H1亚共晶沉积薄壁组织的最大硬度为21.4 GPa，H2亚共晶沉积的最大断裂韧度为4.61 MPa m1/2。发现在高热输入下，随着带状结构的厚度减小，断裂韧性增加。该研究结果为通过激光直接材料沉积获得高质量的 Al2O3-ZrO2 陶瓷提供了一些基础。