Abstract
Finite element analysis was conducted to study the compaction densification mechanism of Fe-40at%Al composite powders. Firstly, the effect of compaction methods on the property of the compact was characterized by finite element simulation and physical experiment. It was shown that the double compaction could obtain denser compacts comparing with that in uniaxial compaction under the same initial conditions. The simulation result was consistent with the experiment result, and they were well fitted with Van Der Zwan-Siskens model. Furthermore, the effect of compaction pressure was analyzed. It was observed that the increase in compaction pressure could improve the relative density and stress of the compact. Finally, the effect mechanism of the die wall friction was analyzed. And a fitting equation of Fe-40at%Al composite powders was proposed on the basis of Van Der Zwan-Siskens model. The results indicated that friction was the primary reason that induced inhomogeneous density and stress distributions.
Highlights
Fe-Al intermetallic compounds with high strength-toweight ratio, excellent anti-corrosion performance, and superior elevated-temperature strength have wide applications in machinery, energy, aerospace and aviation fields.1–4 Due to these physico-chemical properties, Fe-Al intermetallic compounds have attracted considerable attention to many researchers.5–9 Reaction synthesis method that includes the powder compaction and sintering process have been a significant technique to manufacture intermetallic compounds.10–12 It is relatively easy to form and control with low price and high efficiency.13–16 Whereas, researchers have pay more attention to the sintering process, powder compaction as one of paramount steps in powder metallurgy is vital for the properties of the final products.17 This process can produce compacts with certain shape, size, proper density and suitable strength
Densification index, which represents the densification ability of powder when the plastic deformation occured The rate of plastic deformation coefficient Constants, in which B1=lgM, where M represents compaction modulus The magnitude of the pressure at the start of plastic deformation Compaction pressure applied on powder Theoretical density of powder Initial relative density of powder Current relative density of the compact composite powders
The compaction densification mechanism of Fe-40at%Al composite powders was analyzed by finite element (FE) method
Summary
Fe-Al intermetallic compounds with high strength-toweight ratio, excellent anti-corrosion performance, and superior elevated-temperature strength have wide applications in machinery, energy, aerospace and aviation fields. Due to these physico-chemical properties, Fe-Al intermetallic compounds have attracted considerable attention to many researchers. Reaction synthesis method that includes the powder compaction and sintering process have been a significant technique to manufacture intermetallic compounds. It is relatively easy to form and control with low price and high efficiency. Whereas, researchers have pay more attention to the sintering process, powder compaction as one of paramount steps in powder metallurgy is vital for the properties of the final products. This process can produce compacts with certain shape, size, proper density and suitable strength. Researchers have pay more attention to the sintering process, powder compaction as one of paramount steps in powder metallurgy is vital for the properties of the final products.. Han et al studied the compaction process of Fe-Al mixed metal powder under different mass fraction of Al conditions.. Han et al studied the compaction process of Fe-Al mixed metal powder under different mass fraction of Al conditions.18,19 Their results showed that the relative density of the compact increased with increment of Al powder. Wu et al analyzed the effect of packing structures on the densification behavior of FeAl mixed metal powders.20 Both the square and hexagonal initial packing structures were performed. The compact manufactured with this compaction method has non-uniform relative density distribution.21 These defects are negative for the follow-up sintering process. The effect mechanism of die wall friction on the relative density distribution, stress distribution, and the powder flow behavior were analyzed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
