scholarly journals Microstructure Evolution and Recrystallization Resistance of a 7055 Alloy Fabricated by Spray Forming Technology and by Conventional Ingot Metallurgy

2020 ◽  
Vol 51 (10) ◽  
pp. 5378-5388
Author(s):  
Zhiqiang Xie ◽  
Zhihong Jia ◽  
Kaiyun Xiang ◽  
Yaping Kong ◽  
Zhenguo Li ◽  
...  
Keyword(s):  
Microstructure Evolution ◽  
Spray Forming ◽  
Ingot Metallurgy ◽  
Forming Technology ◽  
Conventional Ingot

Electrochemical Impedance Characteristics of Sintered 7075 Aluminum Alloy Under Ssrt Condition

2013 ◽  
Vol 58 (2) ◽  
pp. 505-508 ◽  
Author(s):  
S. Sunada ◽  
N. Nunomura
Keyword(s):  
Aluminum Alloys ◽  
Complex Shape ◽  
Electrochemical Impedance ◽  
Ingot Metallurgy ◽  
View Point ◽  
Corrosion Properties ◽  
Electrochemical Tests ◽  
Impedance Characteristics ◽  
Polarization Test ◽  
Conventional Ingot

Powder metallurgy (P/M) process has the advantage of better formability to fabricate complex shape products without machining and welding. And recently this P/M process has been applied to the production of aluminum alloys. The P/M aluminum alloys thus produced also have received considerable interest because of their fine and homogeneous structure. Many papers have been published on the mechanical properties of the aluminum alloys produced by P/M process while there have been few on their corrosion properties from the view point of electrochemistry. In this experiment, therefore, two kinds of 7075 aluminum alloys prepared by the conventional ingot metallurgy (I/M) process and P/M process were used, I/M material is commercially available. and their corrosion behavior were investigated through the electrochemical tests such as potentiodynamic polarization test, slow rate strain tensile (SSRT) test and electrochemical impedance spectroscopy (EIS) measurement under SSRT test in the corrosion solution and the deionized water.

Effects of Atomizing Gas on Microstructural Characteristics and Mechanical Properties of Spray Formed High Si Steels

2009 ◽  
Vol 620-622 ◽  
pp. 57-60
Author(s):  
Je Sik Shin ◽  
Bong Hwan Kim ◽  
J.G. Lee ◽  
Seung Y. Shin ◽  
Gwang Bo Choi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Spray Forming ◽  
Forming Process ◽  
Microstructural Characteristics ◽  
Steel Sheets ◽  
Conventional Ingot ◽  
Cold Workability ◽  
Ingot Cast

In order to investigate the feasibility of spray forming process for production of high Si steel sheets, 4.8~6.4%Si steels were prepared by spray forming process using N2 and Ar gases and their cold workability was compared with that of conventional ingot cast samples. Atomizing gas affected significant effect on deposit features, microstructural characteristics and mechanical properties of the spray formed high Si steels.

Effects of Initial Rolling Temperature on Rolling Deformation and Microstructure Evolution of 42CrMo Casting Ring Blank

2013 ◽  
Author(s):  
Ju Li ◽  
Yongtang Li ◽  
Huiping Qi ◽  
Huiqin Chen
Keyword(s):  
Dynamic Recrystallization ◽  
Microstructure Evolution ◽  
Rolling Temperature ◽  
Key Factors ◽  
Software Environment ◽  
Forming Technology ◽  
Dynamic Recrystallization Behavior ◽  
3D Software ◽  
Ring Blank ◽  
Rolling Deformation

It is the basis for the new casting-rolling compound forming technology to investigate the rules of rolling deformation and microstructure evolution of casting ring blank. The initial rolling temperature of casting ring blank is one of the key factors influencing deformation and dynamic recrystallization behavior. In this paper, dynamic recrystallization models of as-cast 42CrMo steel were derived from thermo-simulation experimental results. Then, under DEFORM-3D software environment, deformation and dynamic recrystallization of 42CrMo casting ring blank were simulated at different initial rolling temperature by coupled thermo-mechanical finite element method. According to the simulation results, the effects of initial rolling temperature on strain fields distribution and dynamic recrystallization of 42CrMo casting ring blank were discussed. The results show that: (1) increased initial rolling temperature makes plastic deformation expand from ring’s outer and inner-layer to middle and distribute ever more evenly; (2) increased initial rolling temperature can lead to increased dynamic recrystallization fraction, but grain size of ring’s inner and outer-layer becomes smaller and smaller, while that of mid-layer coarser and coarser.

Spray forming technology for military applications

1994 ◽  
Vol 3 (2) ◽  
pp. 197-198 ◽  
Author(s):  
A. Moran ◽  
C. Madden ◽  
R. Rebis ◽  
R. Payne ◽  
M. A. Matteson
Keyword(s):  
Spray Forming ◽  
Forming Technology ◽  
Military Applications

TEM Characterization of Aged Ti-5Al-2.5Sn Powder Metallurgy Alloys with Si and with Ge Additions

1981 ◽  
Vol 39 ◽  
pp. 64-65
Author(s):  
A. G. Jackson ◽  
R. E. Omlor ◽  
R. H. Froes ◽  
J. Moteff
Keyword(s):  
Powder Metallurgy ◽  
Cost Savings ◽  
Ingot Metallurgy ◽  
Potential Cost ◽  
Thin Foils ◽  
Rapid Quench ◽  
Conventional Ingot ◽  
Product Displays ◽  
And Behavior

Titanium alloys produced by the powder metallurgy (PM) techniques are of interest because of the potential cost savings and property enhancement above that possible by conventional ingot metallurgy approaches. In the present program the Ti-5Al-2.5Sn alloy, an all alpha system, is being studied as a model PM titanium alloy. Alloying additions of Si and Ge, which normally result in coarse precipitate regions in cast and wrought material because of their low solubility, have been made. The PM products circumvent the ingot problem because segregation is avoided and precipitates are retained in solution by either the rapid quench rate (pre-alloyed powder) or homogeneous mixing (elemental blend approach). The resulting product displays structures and behavior which differ from conventional Ti-5Al-2.5Sn product. To date Ti-5Al-2.5Sn PM alloys with 0.5 Si and with 1.0Ge w/o have been prepared by an elemental blend/cold compact/sinter process, followed by Hot Isotatic Pressing (HIP'ing). Subsequently specimens were aged at 1000°F (540°C) for 3, 66, and 500 hours in order to precipitate silicides and germanides. Thin foils were then prepared and characterized using TEM and STEM techniques.

Preparation of Mn-Zn Ferrite Flake Absorbent by Self-Reactive Spray Forming Technology

2015 ◽  
Vol 645-646 ◽  
pp. 246-251
Author(s):  
Hai Tao Gao ◽  
Jian Jiang Wang ◽  
Hong Fei Lou ◽  
Xu Dong Cai ◽  
Yong Shen Hou
Keyword(s):  
Crystal Structure ◽  
Formation Mechanism ◽  
Reaction System ◽  
Spray Forming ◽  
Adiabatic Temperature ◽  
Electromagnetic Properties ◽  
Absorption Test ◽  
Spinel Crystal ◽  
Forming Technology ◽  
Zn Ferrite

Fe+MnO +Fe2O3+ZnO reaction system was used to prepare Mn-Zn ferrite flake absorbent by self-reactive spray forming technology. Extrinsic enthalpy (H) and adiabatic temperature (Tad) of system were calculated. The formation mechanism and electromagnetic properties of Mn-Zn ferrite flake absorbent were analyzed. The results show that Tad exceeded 1998K, self-propagation reaction can be ignited and products can be melted. The droplets impacted onto copperplate to achieve flake shape. SEM and XRD were used to characterize the morphology and phase of samples. The results show that most of flake absorbent are at 100μm wide and 10μm thick, and they are constituted by pure Mn0.5Zn0.5Fe2O4 phase with spinel crystal structure. Absorption test show that the absorbent has two absorption peaks, the minimum value of reflectivity is at -27dB and the bandwidth lower than -10dB reaches to 3.5GHz. The Mn-Zn ferrite flake absorbent provides with preferable properties, which is potential in the further investigations.

Microstructure and Properties of Advanced Tool Steels

2019 ◽  
Vol 395 ◽  
pp. 85-94
Author(s):  
Jan Šerák ◽  
Vojtěch Pečinka ◽  
Dalibor Vojtěch
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
High Speed ◽  
Notch Toughness ◽  
Ingot Metallurgy ◽  
Tool Steels ◽  
Soft State ◽  
Conventional Ingot ◽  
Advanced Tool ◽  
Hardened Condition

In this work, the microstructure and mechanical properties of four types of high-speed tool steels (Vanadis 30, Vanadis 60, ASP 2052 and S 705) were studied. The steel S 705 was made by conventional ingot metallurgy technology, and other types of steels were manufactured by powder metallurgy technology. All studied steels were examined both in the soft state and further in the hardened condition with subsequent tempering. Microstructure of metallographic samples and fracture areas was studied by electron microscopy. Hardness, tensile properties and notch toughness were determined. Significant differences in the properties of steels in both studied states were documented.

Sign in / Sign up

Export Citation Format

Share Document