GH4169合金表面氧化色变化行为研究

针对不同温度和时间加热后的GH4169合金试样表面氧化色变化行为进行分析,对试样表面氧化色图片的采集、描述方法进行探讨,并对试样硬度随加热时间的变化进行了研究。结果表明：400～850℃加热后的GH4169合金试样表面均有金属光泽,颜色变化较丰富且与加热温度和时间之间具有一定的对应关系;900～1200℃加热后的试样表面颜色差别不大,均无金属光泽并呈灰黑色;在加热时间相同的情况下,400～800℃加热后的试样硬度值差别不大,850～1200℃加热后,随加热温度的升高试样的硬度值下降较明显;根据试样实际情况,结合试样表面颜色、状态及硬度值的变化可以为判断其经历的温度环境提供可靠的判据,在试样表面具有金属光泽且硬度值差别不大时主要以表面颜色和状态为依据,试样表面无金属光泽且呈灰黑色时则以硬度值为主要判据;此外,采用规范的图片采集过程,利用设计印刷标准色谱对表面氧化色的定量分析和UV加膜印刷技术能够较好地描述合金表面颜色的变化及存在的微小差异。

Color Change of GH4169 Superalloy by High-temperature Oxidation

The color change behavior of GH4169 superalloy by high-temperature oxidation was investigated by acquiring and analyzing the surface color of the samples heat-treated at different temperature for different time.Additionally,the relationship between hardness and heating duration was also investigated.It is manifested that at 400～850 ℃,the surface of GH4169 alloy still presents metallic sheen,and the surface color varies obviously with the variation of temperature and time.At 900～1 200 ℃,the surface of GH4169 alloy presents dark color instead of metallic sheen,and the surface color variation is unobvious.Under the same heating duration,the hardness of GH4169 alloy varies unobviously at 400～800 ℃,but declines obviously with the rise of temperature at 850～1 200 ℃.Surface color and hardness could thus be used as reliable evidences to determine the past temperature environment.Surface color feature can be used as the main criterion when GH4169 alloy shows metallic sheen and undifferentiated hardness,while hardness can act as the main criterion when GH4169 alloy has dark surface.In addition,a standard collecting procedure,a quantitative analysis by chromatogram and a printing technique with UV films can accurately characterize the oxidation color of GH4169 superalloy.