(Ti,Nb)(C,N) precipitate characterization: from hot rolling to girth welding (ETCS)

该合作伙伴关系的目标是在管线钢中形成小TiN和（Ti，Nb）（C，N）沉淀物的加工和微观结构条件方面产生新的知识。后者比前者更不稳定。在热轧期间，TiN是优选的，因为它们固定奥氏体晶界。需要确定TiN而不是（Ti，Nb）（C，N）形成精细分散的条件。此外，确定产生NbC的形成的工艺条件以及这些析出物与韧性的关系也是有意义的。该项目旨在对TiN、（Ti，Nb）（C，N）和NbC析出物的数量、成分、位置和尺寸以及热轧产品和环焊热影响区（HAZ）的组织演变和性能产生新的认识。[1，2]这些管线钢对于在加拿大或国际上运输能源产品至关重要。 这些产品包括石油、天然气、二氧化碳和氢气。因此，本项目将为发起人（EVRAZ、TransCanada Pipelines Limited、CRC Evans、SGS Canada、Acuren和CanmetMATERIALS）提供热轧过程中组织和沉淀物演变以及它们如何影响钢韧性的知识。此外，环焊缝参数与钢材性能之间的关系将为申办方提供有关评估钢材环焊缝适用性的方法的知识，而不仅仅是钢材化学性质。计划对五名HQP进行该项目的培训，以解决这些管线钢的加工组织和性能的作用。

The goal of this partnership is to generate new knowledge on the processing and microstructural conditions forthe formation of small TiN and (Ti,Nb)(C,N) precipitates in pipeline steels. The latter are less stable than theformer. During hot rolling TiN is preferred as they pin down austenite grain boundaries. The conditions wherea fine dispersion of TiN rather than (Ti,Nb)(C,N) forms needs to be determined. In addition, it is of interest toidentify the process conditions that yield the formation of NbC and the relationship of these precipitates totoughness. The project seeks to generate a new understanding of the quantity, composition, location and sizeof TiN, (Ti,Nb)(C,N) and NbC precipitates and the microstructure evolution and properties of hot rolledproduct and girth welded heat affected zone (HAZ).[1,2] These pipeline steels are critical for the transport of energy procucts across Canada or internationally. These products include oil, natural gas, CO2 and hydrogen. This project will, therefore, provide the Sponsors (EVRAZ, TransCanada Pipelines Limited, CRC Evans, SGS Canada, Acuren and CanmetMATERIALS) with knowledge regarding the evolution of structure and precipitates during hot rolling and how they affect steel toughness. Additionally, the relationship between girth weld parameters and steel properties will provide Sponsors with knowledge on ways to assess the suitability of a steel for girth welding beyond simply the steel chemistry. Five HQP are planned to be trained on this project addressing the role of processing-structure and properties of these pipeline steels.