A cost-effective Fe-P-C nanocrystalline alloy(Fe_(85)P_9C_6)was developed via melt-spinning by eliminating expensive alloying elements and post-annealing steps.The microstructure consists of an amorphous matrix with u...A cost-effective Fe-P-C nanocrystalline alloy(Fe_(85)P_9C_6)was developed via melt-spinning by eliminating expensive alloying elements and post-annealing steps.The microstructure consists of an amorphous matrix with uniformly dispersed nanocrystalline clusters,featuring an average size of approximately 5 nm.This dual-phase structure remains thermally stable up to 569 K and results in excellent magnetic and mechanical performance,including a high saturation magnetic induction of 1.69 T,Vickers hardness of 621 HV,and outstanding bending ductility.Crystallization proceeds via the transformation of a metastable fcc-(Fe,P,C)phase intoα-Fe,Fe_(3)C,and Fe_(3)P,driven by internal stress arising from atomic size mismatch.Continuous heating and cooling transformation diagrams further reveal that this process can be precisely controlled to optimize phase evolution.The high Fe content and stress-relaxed nanocrystalline clusters contribute to enhanced in-plane magnetic anisotropy and rapid domain response.This simplified,annealing-free approach not only reduces material and processing costs but also provides a viable pathway for scalable fabrication of next-generation soft magnetic alloys with superior performance and manufacturability.展开更多
Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presen...Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presents significant challenges.In this study,a novel research method was introduced for investigating the solidification process of ductile iron pipe,namely thermal simulation of ductile iron pipe.Comparative research was conducted on the microstructure and properties of the thermal simulation sample and the ductile iron pipe.The findings indicate that the thermal simulation sample and ductile iron pipe exhibit good heat transfer similarity and microstructure similarity.The difference of cooling rate between thermal simulation sample and ductile pipe is less than 0.24℃·s^(-1),and the difference of microstructure content of free cementite,ferrite,and pearlite is less than 5%.The tensile strength of annealed ductile iron pipe is 466 MPa,with an elongation of 16.1%and a Brinell hardness of 156.5 HBW.In comparison,the tensile strength of annealed thermal simulation sample is 482.0 MPa,with an elongation of 15.5%and a Brinell hardness of 159.0 HBW.These results suggest that the thermal simulation experimental research method is both scientific and feasible,offering an objective,reliable,and cost-effective approach to laboratory research on ductile iron pipe.展开更多
基金the support received from the National Natural Science Foundation of China(No.52202213)the Shandong Province Youth Fund(Nos.ZR2024QE439,ZR2024QE532)+2 种基金the Scientific Research Fund of Dezhou University(No.30103540)the China Postdoctoral Science Foundation(No.2023M730905)the Science Research Project of the Hebei Education Department(No.QN2024031)。
文摘A cost-effective Fe-P-C nanocrystalline alloy(Fe_(85)P_9C_6)was developed via melt-spinning by eliminating expensive alloying elements and post-annealing steps.The microstructure consists of an amorphous matrix with uniformly dispersed nanocrystalline clusters,featuring an average size of approximately 5 nm.This dual-phase structure remains thermally stable up to 569 K and results in excellent magnetic and mechanical performance,including a high saturation magnetic induction of 1.69 T,Vickers hardness of 621 HV,and outstanding bending ductility.Crystallization proceeds via the transformation of a metastable fcc-(Fe,P,C)phase intoα-Fe,Fe_(3)C,and Fe_(3)P,driven by internal stress arising from atomic size mismatch.Continuous heating and cooling transformation diagrams further reveal that this process can be precisely controlled to optimize phase evolution.The high Fe content and stress-relaxed nanocrystalline clusters contribute to enhanced in-plane magnetic anisotropy and rapid domain response.This simplified,annealing-free approach not only reduces material and processing costs but also provides a viable pathway for scalable fabrication of next-generation soft magnetic alloys with superior performance and manufacturability.
基金financially supported by the National Natural Science Foundation of China(52130109)。
文摘Centrifugal casting of ductile iron pipe is a high-temperature,semi-continuous production process.However,conducting laboratory research on the solidification process of centrifugal casting of ductile iron pipe presents significant challenges.In this study,a novel research method was introduced for investigating the solidification process of ductile iron pipe,namely thermal simulation of ductile iron pipe.Comparative research was conducted on the microstructure and properties of the thermal simulation sample and the ductile iron pipe.The findings indicate that the thermal simulation sample and ductile iron pipe exhibit good heat transfer similarity and microstructure similarity.The difference of cooling rate between thermal simulation sample and ductile pipe is less than 0.24℃·s^(-1),and the difference of microstructure content of free cementite,ferrite,and pearlite is less than 5%.The tensile strength of annealed ductile iron pipe is 466 MPa,with an elongation of 16.1%and a Brinell hardness of 156.5 HBW.In comparison,the tensile strength of annealed thermal simulation sample is 482.0 MPa,with an elongation of 15.5%and a Brinell hardness of 159.0 HBW.These results suggest that the thermal simulation experimental research method is both scientific and feasible,offering an objective,reliable,and cost-effective approach to laboratory research on ductile iron pipe.
