TY - JOUR
T1 - Development of niobium powder injection molding. Part II
T2 - Debinding and sintering
AU - Aggarwal, Gaurav
AU - Smid, Ivi
AU - Park, Seong Jin
AU - German, Randall M.
N1 - Funding Information:
The authors gratefully acknowledge the Ben Franklin Technology Development Authority for funding this research through the Center for Innovative Sintered Products.
PY - 2007/5
Y1 - 2007/5
N2 - This article is a continuation of feedstock preparation and powder injection molding (PIM) of pure niobium. Part II discusses debinding and sintering of injection molded niobium. PIM of pure niobium powder was analyzed for efficiency of the process. After solvent and thermal debinding, sintering of injection molded material was conducted up to 2000 °C in vacuum as well as inert-gas low-oxygen partial pressure atmosphere. This paper investigates the effect of sintering time, temperature and atmosphere on the processing of pure niobium. Under all sintering conditions the oxygen content is reduced from ∼19,000 in the as-received powder to as low as 300 ppm, at e.g. 2000 °C for 2 h in a low-vacuum atmosphere. The carbon content increased from the as-received 70 to 200-300 ppm, depending on the sintering conditions. However, this amount of carbon is not considered detrimental for structural application. Master decomposition and sintering curves are introduced for pure niobium to study the optimum debinding and sintering conditions. Further, sintering parameters (atmosphere, peak temperature and hold time) are optimized for achieving maximum densities with minimal impurities.
AB - This article is a continuation of feedstock preparation and powder injection molding (PIM) of pure niobium. Part II discusses debinding and sintering of injection molded niobium. PIM of pure niobium powder was analyzed for efficiency of the process. After solvent and thermal debinding, sintering of injection molded material was conducted up to 2000 °C in vacuum as well as inert-gas low-oxygen partial pressure atmosphere. This paper investigates the effect of sintering time, temperature and atmosphere on the processing of pure niobium. Under all sintering conditions the oxygen content is reduced from ∼19,000 in the as-received powder to as low as 300 ppm, at e.g. 2000 °C for 2 h in a low-vacuum atmosphere. The carbon content increased from the as-received 70 to 200-300 ppm, depending on the sintering conditions. However, this amount of carbon is not considered detrimental for structural application. Master decomposition and sintering curves are introduced for pure niobium to study the optimum debinding and sintering conditions. Further, sintering parameters (atmosphere, peak temperature and hold time) are optimized for achieving maximum densities with minimal impurities.
UR - http://www.scopus.com/inward/record.url?scp=33846582386&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33846582386&partnerID=8YFLogxK
U2 - 10.1016/j.ijrmhm.2006.05.005
DO - 10.1016/j.ijrmhm.2006.05.005
M3 - Article
AN - SCOPUS:33846582386
SN - 0958-0611
VL - 25
SP - 226
EP - 236
JO - International Journal of Refractory Metals and Hard Materials
JF - International Journal of Refractory Metals and Hard Materials
IS - 3
ER -