以高纯钨粉为原料，通过等静压和烧结成型，烧结温度2300℃，然后再在轧机上进行轧制，分别制备出T5 mm超高纯钨板。对高纯钨板进行热处理，热处理温度1000-2000℃，升温速度100-200℃/s，热处理之后分别线切割取样10*10*T（避开边缘20mm），然后六面磨光，并在25%高氯酸和75％的酒精混合溶液中，以10±2 V的电压和45±5 A的电流进行电解抛光，持续时间为50-120 s。最后在LEICA金相显微镜下进行金相和平均晶粒尺寸的检测。参考标准：GB/T 3488.2和GB/T 6394。

Using high purity tungsten powder as raw material, T5 mm ultra high purity tungsten plate was prepared by isostatic pressing and sintering at 2300℃ and then rolling on a rolling mill. High purity tungsten plate was heat treated at 1000-2000℃ and heating rate 100-200℃/s. After heat treatment, 10*10*T samples were taken by wire cutting respectively (avoiding the edge by 20mm), and then six sides were polished. In 25% perchloric acid and 75% alcohol mixed solution, Electrolytic polishing was performed at A voltage of 10±2 V and A current of 45±5 A for A duration of 50-120 s. Finally, metallography and average grain size were measured under LEICA metallography microscope. Reference standard: GB/T 3488.2 and GB/T 6394.