本发明提供一种表征钛及钛合金超大晶粒的方法，包括：对钛及钛合金样品进行阳极氧化，对阳极氧化染色后的样品表面进行拍照；氧化染色后的样品有若干种颜色，从每种颜色区域选取至少两块作为代表样品，进行X射线衍射，得到代表样品的晶相；其它与代表样品颜色相同的区域的晶相与相应代表样品的晶相相同；如果某一颜色区域代表样品表面的衍射谱线强度较小，无法形成衍射，则补充进行极图实验，测定该颜色区域代表样品的单相性及取向；其它与代表样品颜色相同的区域的晶相与相应代表样品的单相性及取向相同。本发明构思巧妙，在表征表面形貌的同时，通过X射线衍射实验及极图实验确定晶粒的取向，可广泛用于类似EB炉铸造钛锭超大晶粒铸态组织的表征。

The invention provides a method for characterizing super large crystal grains of titanium and titanium alloy. The method comprises the following steps: subjecting titanium and titanium alloy samples to anodization and taking photos of the surfaces of the samples having undergone anodization coloring; as the samples having undergone anodization coloring have a plurality of colors, selecting at least two blocks from each color region as representative samples, and carrying out X-ray diffraction so as to obtain the crystal phase of the representative samples, wherein crystal phases in other regions with the same color as the representative samples are the same as the crystal phases of the corresponding representative samples; and if representative samples in a certain color region are low insurface diffraction spectral line intensity and diffraction cannot be formed, carrying out a supplementary pole diagram experiment to determine the monophase property and orientation of the representative samples in the color region, wherein crystal phases in other regions with the same color as the representative samples have the same monophase property and orientation as the monophase property and orientation of the corresponding representative samples. The method of invention is ingenious in design, can determine the orientation of crystal grains through X-ray diffraction experiment and pole diagram experiments while characterizing surface topography, and can be widely used for characterizing the as-cast structures of super large crystal grains of titanium ingots casted in an EB furnace.