A large campaign of characterization of the ductile to brittle transition temperature (DBTT) and microstructure has been performed on several commercial and lab-scale pure tungsten grades, potassium doped tungsten alloys, and particle reinforced tungsten grades (with particles of TiC, Y₂O₃, or ZrC), all integrated in a large-scale neutron irradiation campaign. The DBTT is deduced based on miniaturized three-point bending tests to provide reference data for the assessment of the irradiation effects on the tungsten alloys. This miniaturized geometry is designed to minimize the operational cost of neutron irradiation, to speed up post-irradiation examination, and to reduce the amount of nuclear waste. The resulting DBTT ranges from around −15 up to 450 °C, depending on the material. The potassium doped tungsten alloys have the lowest DBTT, followed by rolled ZrC reinforced tungsten grade, commercial pure tungsten grades, lab-scale pure tungsten grades, and other particle reinforced tungsten grades. The crack plane orientation and microstructure with respect to grain shape and grain boundaries significantly affect the DBTT for forged/rolled tungsten products with elongated grains. The L-T orientation has a lower DBTT compared to the T-L orientation. Moreover, the DBTT difference in the L-T and T-L orientation raises with increasing the grain aspect ratio. An attempt is made to establish a relationship between the density of low and high angle grain boundaries and DBTT value. The obtained relationship is discussed in the frame of mechanical processing (i.e., rolling or forging) to optimize the DBTT by optimized manufacturing. The results are compared to recent computational predictions of the DBTT in tungsten.

在几种商业和实验室规模的纯钨等级，掺杂钾的钨合金和颗粒增强钨等级（含TiC，Y ₂ O粒子）上，进行了表征韧性至脆性转变温度（DBTT）和微观结构的大型活动。₃（或ZrC），都整合在大规模的中子辐照活动中。DBTT是基于微型三点弯曲试验推论得出的，可为评估对钨合金的辐照效果提供参考数据。设计这种最小化的几何形状可最大程度地减少中子辐照的运营成本，加快辐照后检查的速度，并减少核废料的数量。取决于材料，最终的DBTT范围约为-15至最高450°C。掺钾的钨合金的DBTT最低，其次是轧制ZrC增强钨等级，商业纯钨等级，实验室规模的纯钨等级和其他颗粒增强钨等级。关于晶粒形状和晶界的裂纹平面取向和微观结构显着影响具有细长晶粒的锻造/轧制钨产品的DBTT。与TL方向相比，LT方向的DBTT较低。此外，随着晶粒长径比的增加，LT和TL方向上的DBTT差也增加。试图建立低角度晶界和高角度晶界的密度与DBTT值之间的关系。在机械加工（即轧制或锻造）框架中讨论了获得的关系，以通过优化制造来优化DBTT。将结果与钨中DBTT的最新计算预测进行了比较。LT和TL取向的DBTT差随晶粒长宽比的增加而增加。试图建立低和高角度晶界的密度与DBTT值之间的关系。在机械加工（即轧制或锻造）框架中讨论了获得的关系，以通过优化制造来优化DBTT。将结果与钨中DBTT的最新计算预测进行了比较。LT和TL取向的DBTT差随晶粒长宽比的增加而增加。试图建立低和高角度晶界的密度与DBTT值之间的关系。在机械加工（即轧制或锻造）框架中讨论了获得的关系，以通过优化制造来优化DBTT。将结果与钨中DBTT的最新计算预测进行了比较。