Effect of Sequential Helium and Nickel Ion Implantation on the Nano-Indentation Hardness of X750 Alloy

2020 ◽  
Author(s):  
Maisaa Tawfeeq ◽  
Robert Klassen
Keyword(s):  
Total Hardness ◽  
Indentation Hardness ◽  
Nickel Ion ◽  
Helium Bubbles ◽  
Defect Clusters ◽  
Microstructural Damage ◽  
Heat Treated ◽  
Clear Increase ◽  
Hardness Values ◽  
Inconel X750

Abstract Sequential He+ and Ni+ implantations were performed to investigate their combined effect on the indentation hardness of heat-treated Inconel X750 alloy. The microstructure of the ion-implanted region was also characterized with TEM. The alloy displayed a pronounced softening with very low Ni+ implantation levels, ? = 0.01 - 1.0 dpa, however it showed a clear increase in hardness when implanted with He+ up to CHe = 5000 appm. Samples subjected to sequential He+ and Ni+ implantations displayed hardness values between those presented by sole He+ or Ni+ implantation suggesting that the effects of ion-induced microstructural damage and helium accumulation on the hardness of this alloy can be considered as independent and additive over the range of conditions studied. This observation is in contradiction to previously reported TEM studies which suggest that accumulated helium slows the dissolution/disordering of the ?' hardening phase in this alloy. In our study, established theories were applied to assess the contribution of ion-induced defect clustering, ?' precipitate disordering, and helium bubble accumulation to the hardness of the X750 alloy. It was observed that generation of ion-induced defect clusters and the formation of helium bubbles increased the indentation hardness slightly while the disordering of ?' precipitates resulted in a dramatic decrease in the total hardness. Ni+ and He+ implantation also had different effects on the depth dependence of the indentation hardness (ISE). ISE was pronounced in the samples subjected to Ni+ implantation while it was almost absent in samples subjected to He+.

Ni+ and He+ Implantation Effects on the Hardness and Microstructure of Heat-Treated X750 Superalloy

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Maisaa N. Tawfeeq ◽  
Robert J. Klassen
Keyword(s):  
Electron Microscopy ◽  
Indentation Hardness ◽  
Hardness Testing ◽  
Strengthening Phase ◽  
Tem Analysis ◽  
Helium Bubbles ◽  
Implantation Damage ◽  
Transmission Electron ◽  
Heat Treated ◽  
Helium Ion

Abstract Nickel and Helium ion implantation-induced hardening and microstructural evolution of X750 in the heat-treated (HT) and solution annealed (SA) conditions were investigated using nano-indentation hardness testing and electron microscopy (scanning electron microscopy (SEM) and transmission electron microscopy (TEM)). Irradiation crystal damage up to ψ = 5 dpa was invoked with Ni+ implantation while He+ implantation up to CHe = 5000 appm was performed on samples the HT and SA conditions. The X750 alloy displayed generally increasing hardness with increasing Ni+ implantation damage but a perturbation in the trend occurred when ψ ≤ 0.5 dpa, and the hardness dropped by about 30% and 2% for the HT and the SA samples, respectively. TEM analysis indicated that this softening was associated with disordering and dissolution of the γ′ strengthening phase. The hardening behavior observed at higher implantation damage (ψ = 1 dpa) resulted in reformation of Al/Ti-rich regions within the microstructure phase. The hardness of the X750 increased continuously with increasing implanted He+ up to CHe = 1000 appm. This was associated with the formation of helium bubbles as observed by TEM. Slight drop in hardness in the HT condition at CHe = 5000 appm indicated that high levels of He+ implantation destabilize the γ′ precipitates as was confirmed with TEM observed disappearance of γ′ super-lattice reflections.

Effects of deep cryogenic treatment on machinability, hardness and microstructure in dry turning process of tempered steels

2020 ◽  
pp. 095440892097944
Author(s):  
Menderes Kam
Keyword(s):  
Cryogenic Treatment ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Point Of View ◽  
Turning Process ◽  
Deep Cryogenic Treatment ◽  
Dry Turning ◽  
Control Factors ◽  
Heat Treated ◽  
Hardness Values

This study investigated the effects of Deep Cryogenic Treatment (DCT) on machinability, hardness, and microstructure in dry turning process of AISI 4140 (48-51 HRc) tempered steels with ceramic cutting tools on the surface roughness (Ra). DCT process of steels has shown significant improvement in their mechanical properties. In this context, experiments were made with Taguchi L16 method and optimum values were determined. Three different values for each control factors as: different heat treated samples, cutting speeds (160, 200, 240, 280 m/min), feed rates (0.08, 0.12, 0.16, 0.20 mm/rev) were selected. As a result, the lowest Ra value was found to be 0.159 µm for the DCTT36 sample at a cutting speed of 240 m/min, a feed rate of 0.08 mm/rev. The optimum Ra value was the lowest for the DCTT36 sample compared to the other samples as 0.206 µm. The hardness values of the micro and macro were highest for the DCTT36 sample. Microstructural point of view Scanning Electron Microscopy (SEM) point of view, the DCCT36 sample showed that best results owing to its homogeneity. It was concluded that lower Ra values can be obtained with ceramic cutting tool in dry turning experiments according to the studies in the literature review. It is thought to be preferred as an alternative to cylindrical grinding process due to lower cost.

Effect of Heat Treatment on the Properties of (Fe0.6Co0.4)71Si5Nb4B20 Bulk Metallic Glass

2021 ◽  
Vol 875 ◽  
pp. 70-75
Author(s):  
Syed Zameer Abbas ◽  
Rashid Ali ◽  
Syed Muttahir Shah ◽  
Owais Jan ◽  
Munim Awan
Keyword(s):  
Glass Transition ◽  
Metallic Glass ◽  
Bulk Metallic Glass ◽  
Cast Alloy ◽  
Amorphous Structure ◽  
Indentation Hardness ◽  
Alloy Sample ◽  
Scanning Calorimetry ◽  
Heat Treated Sample ◽  
Heat Treated

Bulk metallic glasses (BMGs) are an important class of materials with unique set of properties. A bulk metallic glass with composition of (Fe0.6Co0.4)71Nb4Si5B20 was cast in the form of a 1 mm thick strip in a water cooled copper mold. The BMG produced was characterized for structure, thermal and mechanical properties. The X-ray diffraction performed on the as cast alloy has shown completely amorphous structure. The glass transition and crystallization peak temperatures obtained through differential scanning calorimetry scan were 542 °C and 588.4 °C, respectively. Some cast amorphous alloy sample was annealed below glass transition (450 °C for 30 mi93nutes) and others above glass transition (580 °C for 5 minutes) temperatures. Nano- indentation hardness of 13.3 GPa was obtained for as cast alloy while a hardness values of 12.8 and 15.84 GPa were measured for heat treated alloys at temperature of 450 °C and 580 °C, respectively. Increase in hardness was attributed to formation of crystals in an amorphous matrix whereas decrease in hardness was due to relaxation of quenching residual stresses. The maximum value of elastic modulus obtained through indentation was 255 GPa for 580 °C heat treated sample.

The new mineral insizwaite (PtBi2) and new data on niggliite (PtSn)

1972 ◽  
Vol 38 (299) ◽  
pp. 794-800 ◽  
Author(s):  
L. J. Cabri ◽  
D. C. Harris
Keyword(s):  
New Mineral ◽  
Indentation Hardness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Reflected Light ◽  
D 12 ◽  
Probable Space ◽  
Micro Indentation ◽  
Hardness Values ◽  
Reflectance Measurements

SummaryInsizwaite from Waterfall Gorge, Insizwa, is a new mineral with the composition Pt1·00Bi1·35Sb0·57. The name is for the locality and is to be applied to the end member PtBi2. The analysed material is an antimonian variety. The mineral is cubic, the unit-cell for the antimonian variety has a 6·625 (2) Å, probable space group Pa3, calc. D 12·8 g/cm3. The strongest lines on the X-ray diffraction powder pattern are: 2·96 (8) 210; 2·70 (8) 211; 2·34 (5) 220; 1·99 (10 311; 1·774 (7) 321; 1·433 (5) 421; 1·277 (6) 511, 333; 1·171 (6) 440; and 0·862 (7) 731. Under reflected light the mineral is white (in air and in oil) and is isotropic. Reflectance measurements at 470, 546, 589, and 650 nm gave 61·1, 60·0, 60·6, and 61·7 %. Micro-indentation hardness values range from 488 to 540 (av. 519) kg/mm2 with a 25 g load.New data are presented for niggliite from the type locality and for synthetic PtSn.

Structure–property relationships of PCGTA welds of Inconel X750 in as-welded and post-weld heat treated conditions—A comparative study

2015 ◽  
Vol 20 ◽  
pp. 1-14 ◽  
Author(s):  
K. Devendranath Ramkumar ◽  
S. Rahul Krishnan ◽  
R. Ramanand ◽  
S. Logesh ◽  
Tushar Satyandas ◽  
...  
Keyword(s):  
Comparative Study ◽  
Structure Property ◽  
Structure Property Relationships ◽  
Heat Treated ◽  
Inconel X750 ◽  
Weld Heat

scholarly journals Investigation of microstructural damage to eutectic carbides from scratch tests of a heat-treated Fe–Cr–W–Mo–V–C alloy

Wear ◽  
2016 ◽  
Vol 358-359 ◽  
pp. 137-147 ◽  
Author(s):  
Jing Guo ◽  
Yunli Feng ◽  
Ligang Liu ◽  
Xiaolei Xing ◽  
Xuejun Ren ◽  
...  
Keyword(s):  
Eutectic Carbides ◽  
Microstructural Damage ◽  
Heat Treated ◽  
Scratch Tests

Improvement of the Mechanical Properties of Glasses Based on the 3CaO.P2O5-SiO2-MgO System after Heat-Treatment

2010 ◽  
Vol 636-637 ◽  
pp. 41-46 ◽  
Author(s):  
J.K.M.F. Daguano ◽  
Claudinei dos Santos ◽  
Paulo Atsushi Suzuki ◽  
Luiz A. Bicalho ◽  
Maria Helena F.V. Fernandes
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Glass Ceramics ◽  
Xrd Analysis ◽  
Phase Content ◽  
Heat Treated ◽  
Different Temperatures ◽  
Hardness Values ◽  
Crystallization Degree ◽  
Temperature Crystallization

Glasses based on the 3CaO.P2O5-SiO2-MgO system present high bioactivity aiming the use as bone restorations. On the other hand, the low mechanical properties reduce the importance of this glass aiming the use as restoration bulk specimens. In this work, glass-ceramics were obtained by devitrification of this glass using different temperatures. CaCO3, SiO2, MgO and Ca(H2PO4).H2O were used as starting-powders. Powder mixture was milled/homogenized and melted at 1600°C, for 2h and annealed at 700°C for 4h with cooling rate of 3°C/min. Glass specimens of 151550mm3 were characterized by DTA and XRD analysis. Specimens were heat-treated in different temperatures between 7000C and 1050°C, for 4 hours, obtaining glass-ceramics with different crystallized phase content. Hardness and fracture toughness were determined and correlated with crystalline phase content. The results indicated that crystallization-degree increase with the temperature, and the mechanical properties are improved: Hardness values present increases lower than 20% as function of the crystallization. Fracture toughness may increase 100% as function of temperature (crystallization degree).

scholarly journals Effect of Thermal Ageing Characteristics of Al-Si-Fe/Sic Particulate Composite Synthesized by Double Stir Casting

2010 ◽  
Vol 7 (1) ◽  
pp. 53 ◽  
Author(s):  
V.S. Aigbodion ◽  
S.B. Hassan
Keyword(s):  
Impact Energy ◽  
Ageing Time ◽  
Particulate Composite ◽  
Stir Casting ◽  
Thermal Ageing ◽  
Reinforced Composite ◽  
Heat Treated ◽  
Particulate Reinforced ◽  
Hardness Values ◽  
Composite Samples

 The effect of thermal ageing on the microstructure and properties of 10wt% and 20wt%SiC particulate reinforced Al-Si-Fe matrix composite, produced by double stir casting route, have been studied. The composite samples were solution heat-treated at 500o C for 3 hrs and aged at 100, 200, and 300o C with ageing time between 60 and 660 minutes. The ageing characteristics of these grades of composite were evaluated using hardness values, impact energy, tensile properties and microstructure. The tensile strength, yield strength, hardness values increased as the percentage of silicon carbide increased in the alloy with decreased impact energy in both the as-cast and thermally age-hardened samples. The increases in hardness values and strength during thermal ageing are attributed to the formation of coherent and uniform precipitation in the metal lattice. It was found that both grades of composites showed acceleration in thermal ageing compared to the monolithic alloy. However, the 20wt%SiC reinforced composite showed more acceleration compared to 10wt%SiC reinforced composite. 

Sign in / Sign up

Export Citation Format

Share Document