Figure 4. Ex-situ electric field XRD patterns of (A) WCBN and (B) WCBN-1000HT ceramics. (C) I200/I020 of the WCBN and WCBN-1000HT ceramics under ex-situ electric field. PFM phase images of the (D) WCBN and (E) WCBN-1000HT ceramics were measured under voltages of 10 and 20 V.