Low-temperature plasma nitriding of AISI 304 stainless steel with nano-structured surface layer

Zhang, H. W.; Wang, Lin; Hei, Z. K.; Liu, G.; Lü, Jian; Lu, K.

doi:10.3139/146.031143

Cited by 33 publications

(23 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, Tong and Zhang showed that the gaseous nitriding of a SMATed pure iron plate and the plasma nitriding of a SMATed AISI 304 stainless steel specimen were also achieved recently at 300 • C and 400 • C, respectively. These temperatures are evidently lower than those in conventional nitriding processes (500-550 • C) [9,10]. In addition, the experiment of chromizing behaviors of the SMATed steel sample showed that the formation temperature of chromium compounds was found to be much lower and the amount of chromium carbides was higher than those in the coarse-grained counterpart [11].…”

Section: Introductionmentioning

confidence: 78%

“…Using SMAT, different microstructures can be obtained within the deformed surface layer through the depth from the treated surface to the strain-free matrix, i.e., from nano-sized grains to sub-micro-sized and micro-sized crystalline on a bulk material [1,[3][4][5][6]. Previous studies showed that the atom diffusion ability on SMATed materials was significantly enhanced due to the formation of a large number of grain boundaries or other defects (vacancy, dislocation and interfaces) by SMAT [9][10][11][12][13][14]. For example, Tong and Zhang showed that the gaseous nitriding of a SMATed pure iron plate and the plasma nitriding of a SMATed AISI 304 stainless steel specimen were also achieved recently at 300 • C and 400 • C, respectively.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Fabrication of Microalloy Nitrided Layer on Low Carbon Steel by Nitriding Combined with Surface Nano-Alloying Pretreatment

Sun

Yao

2016

Coatings

View full text Add to dashboard Cite

Surface mechanical attrition treatment (SMAT) is an effective method to accelerate the nitriding process of metallic materials. In this work, a novel technique named surface nano-alloying (SNA) was developed on the basis of surface mechanical attrition treatment, which was employed as a pretreatment for the nitriding of low carbon steel materials. The microstructure and surface properties of treated samples were investigated by SEM, XRD, TEM and the Vickers hardness test. Experimental results showed that a surface alloying layer (Cr element) of about 10-20 µm in thickness was formed on the low carbon steel sample after the surface nano-alloying treatment. After nitriding for the SNA sample, a complex compound layer composed of Fe 2-3 N, FeCr and Cr 2 N phases was fabricated. Moreover, the thickness of this compound layer was about 50 µm. Meanwhile, both the surface hardness and wear resistance of the SNA nitrided sample are better that those of the SMAT nitrided sample. This work offers a new approach for improving the nitriding process of steel materials.

show abstract

Section: Introductionmentioning

confidence: 78%

Section: Introductionmentioning

confidence: 99%

Fabrication of Microalloy Nitrided Layer on Low Carbon Steel by Nitriding Combined with Surface Nano-Alloying Pretreatment

Sun

Yao

2016

Coatings

View full text Add to dashboard Cite

show abstract

“…The "nc steel" samples were obtained by subsequently coating the nt-ufc steel samples with a nitriding layer [12], further refining the grains to the nanoscale [58]. The plasma nitriding was accomplished at 450 °C for 1.5 h on both sides-see, for example, the evolution of the nanocrystallization for different SMAT durations coupled to plasma nitriding in Fig.…”

Section: Steelmentioning

confidence: 99%

Ballistic performance of nanocrystalline and nanotwinned ultrafine crystal steel

et al. 2012

View full text Add to dashboard Cite

Because of their remarkable mechanical properties, nanocrystalline metals have been the focus of much research in recent years. Refining their grain size to the nanometer range (<100 nm) effectively reduces their dislocation mobility, thus achieving very high yield strength and surface hardness-as predicted by the Hall-Petch relation-as well as higher strain-rate sensitivity. Recent works have additionally suggested that nanocrystalline metals exhibit an even higher compressive strength under shock loading. However, the increase in strength of these materials is generally accompanied by an important reduction in ductility. As an alternative, efforts have been focused on ultrafine crystals, i.e. polycrystals with a grain size in the range of 500 nm to 1 \im, in which "growth twins" (twins introduced inside the grain before deformation) act as barriers against dislocation movement, thus increasing the strength in a similar way as nanocrystals but without significant loss of ductility. Due to their outstanding mechanical properties, both nanocrystalline and nanotwinned ultrafine crystalline steels appear to be relevant candidates for ballistic protection. The aim of the present work is to compare their ballistic performance against coarse-grained steel, as well as to identify the effect of the hybridization with a carbon fiber-epoxy composite layer. Hybridization is proposed as a way to improve the nanocrystalline brittle properties in a similar way as is done with ceramics in other protection systems. The experimental campaign is finally complemented by numerical simulations to help identify some of the intrinsic deformation mechanisms not observable experimentally. As a conclusion, nanocrystalline and nanotwinned ultrafine crystals show a lower energy absorption than coarse-grained steel under ballistic loading, but under equal impact conditions with no penetration, deformation in the impact direction is smaller by nearly 40%. This a priori surprising difference in the energy absorption is rationalized by the more important local contribution of the deviatoric stress vs. volumetric stress under impact than under uniaxial deformation. Ultimately, the deformation advantage could be exploited in the future for personal protection systems where a small deformation under impact is of key importance.

show abstract

“…Thereinto, K. Lu et al 5) have developed a new approach named surface self-nanocrystallization (SSNC) to prepare bulk nc materials, the nc materials from the technology include a large volume fraction of stored energy and nonequilibrium defective such as dislocations, vacancy, subboundary, which may promote chemical reaction of different atoms and enhance atomic diffusion coefficient. 6,7) The SSNC has been applied to chemical heat treatment of many metal materials, research results [8][9][10][11][12][13] show that atomic diffusion coefficient is greatly enhanced in the nanostructured surface layer under low temperature, at the same time, heat treatment time is shorten greatly, which inaugurate new path for low-temperature and high-efficiency chemical heat treatment of metal materials.…”

Section: Introductionmentioning

confidence: 99%

Pulse Pressuring Diffusion Bonding of Ti Alloy/Austenite Stainless Steel Processed by Surface Self-nanocrystallization

et al. 2009

View full text Add to dashboard Cite

Nanostructured surface layers were synthesized on the end face of Ti-4Al-2V titanium alloy and 0Cr18Ni9Ti austenite stainless steel rods by means of high energy shot peening (HESP). Making treated end surfaces as bonding interfaces, Ti-4Al-2V and 0Cr18Ni9Ti rods were bonded by pulse pressuring diffusion bonding (PPDB) on Gleeble-1500D tester at 650-750°C. Joints were tested on tensile testing machine, the fractures and microstructures of joints were researched. Results showed that the maximum tension strength of 262.0 MPa was achieved, cleavage fracture took place while tension test of joints, and the grains in the vicinity of the diffusion layer are fined. But, brittle intermetallic compounds were absence on the bonding interface.KEY WORDS: titanium alloy; stainless steel; pulse pressuring diffusion bonding (PPDB); intermetallic compound.

show abstract

Low-temperature plasma nitriding of AISI 304 stainless steel with nano-structured surface layer

Cited by 33 publications

References 17 publications

Fabrication of Microalloy Nitrided Layer on Low Carbon Steel by Nitriding Combined with Surface Nano-Alloying Pretreatment

Fabrication of Microalloy Nitrided Layer on Low Carbon Steel by Nitriding Combined with Surface Nano-Alloying Pretreatment

Ballistic performance of nanocrystalline and nanotwinned ultrafine crystal steel

Pulse Pressuring Diffusion Bonding of Ti Alloy/Austenite Stainless Steel Processed by Surface Self-nanocrystallization

Contact Info

Product

Resources

About