Guarantee on Fatigue Reliability of Multi-Layered DLC-Coating Given to CD-Carburized SCM415

In this research, surface modification was given to CD (Carbide Dispersion)-carburized steel used for sliding parts of vehicles, and functional evaluation was performed. It developed the DLC-coating which has multi-layered structure according to a UBMS (UnBalance-Magnetron-Sputtering) process as aims at improvement in the tribological properties in the sliding parts for vehicles. In order to maintain the adhesion with parent material (CD-carburized steel), intermediate layer that gradient hardness was generated. Structure of multi-layered part was made into ten layers. The multi-layered part consists of soft layers and hard layers. A soft layer bears high-ductility and the hard layer bears wear resistance and tribological property. Moreover, as functional evaluation of coating material, it investigated about the friction wear characteristic and influence that a DLC-coating has on the fatigue characteristic.

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Improving surface finish and wear resistance of additive manufactured nickel-titanium by ultrasonic nano-crystal surface modification

Journal of Materials Processing Technology ◽

10.1016/j.jmatprotec.2017.06.038 ◽

2017 ◽

Vol 249 ◽

pp. 433-440 ◽

Cited By ~ 37

Author(s):

Chi Ma ◽

Mohsen Taheri Andani ◽

Haifeng Qin ◽

Narges Shayesteh Moghaddam ◽

Hamdy Ibrahim ◽

...

Keyword(s):

Wear Resistance ◽

Surface Modification ◽

Surface Finish ◽

Crystal Surface ◽

Nickel Titanium ◽

Nano Crystal

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Reduction in Wear Rate of α-Alumina and Silicon Nitride by Diffusional Surface Modification

MRS Proceedings ◽

10.1557/proc-140-293 ◽

1988 ◽

Vol 140 ◽

Cited By ~ 1

Author(s):

A.K. Gangopadhyay ◽

M.E. Fine ◽

H.S. Cheng

Keyword(s):

Wear Resistance ◽

Thermal Expansion ◽

Surface Modification ◽

Silicon Nitride ◽

Thermal Expansion Coefficient ◽

Expansion Coefficient ◽

Surface Region ◽

Lattice Parameter ◽

Lower Thermal Expansion ◽

Wear Modes

AbstractThe surface regions of α-alumina and hot pressed silicon nitride were modified by suitable alloying in order to improve their wear resistance. The surface modification in polycrystalline α-alumina was done by diffusing chromia into the surface region which resulted in the formation of a thin layer of A12O3 - Cr9O3 solid solution which has a lower thermal expansion coefficient than pure α-alumina. Also Cr2O3 has a larger lattice parameter than α-alumina thus during cooling the surface was put into compression. The surface region of hot pressed silicon nitride was modified by diffusing α-alumina into the surface which resulted in the formation of a thin sialon layer. A surface compressive stress was again introduced due to the lower thermal expansion coefficient and larger latticeparameter of sialon compared to silicon nitride.Wear tests were conducted against 52100 steel under both lubricated and unlubricated sliding contact using a block on ring apparatus. The wear resistance of chromia surface alloyed α-alumina was improved considerably over unalloyed α-alumina under both lubricated and unlubricated conditions. The wear resistance of alumina surface alloyed silicon nitride was also improved over unalloyed silicon nitride under both lubricated and unlubricated conditions.Different wear modes were identified by examining the worn surfaces under the scanning electron microscope.

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HVOF- and VPS-Coatings Using Nanostructured Iron-Based Alloys

Thermal Spray 1997: Proceedings from the United Thermal Spray Conference ◽

10.31399/asm.cp.itsc1997p0875 ◽

1997 ◽

Author(s):

O.C. Brandt ◽

S. Siegmann ◽

H.-P. Isch

Keyword(s):

Wear Resistance ◽

Corrosion Resistance ◽

Thermal Spraying ◽

High Ductility ◽

High Toughness ◽

Iron Based

Abstract In thermal spraying, Fe-based alloys are often applied for relatively thick and inexpensive coatings. The main advantage of the Fe-based alloy coatings is their high ductility as compared to ceramic and hardmetal coatings. Other advantages such as high toughness, easy machineability and satisfactory corrosion resistance are characteristic of Fe-based alloys. The wear resistance is not outstanding, but nevertheless acceptable for a large number of applications. A further improvement of the wear resistance can be achieved by reinforcing the Fe-based alloy coatings, e.g. by addition of nitrogen to the spraying powder.

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Surface modification of die steels with B—Al-layers by thermal-chemical treatment

10.36652/1813-1336-2021-17-12-557-564 ◽

2021 ◽

pp. 557-564

Author(s):

N.S. Ulakhanov ◽

U.L. Mishigdorzhiyn ◽

A.G. Tikhonov ◽

A.I. Shustov ◽

A.S. Pyatykh

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Surface Layer ◽

Surface Modification ◽

High Temperature ◽

Chemical Treatment ◽

Quality Parameters ◽

Processing Temperature ◽

Die Steels ◽

Composite Layers

The effect of diffusion high-temperature boroaluminizing (HBA) on the mechanical properties and quality parameters of the surface layer of stamp steels 5KhNM and 3Kh2V8F is shown. An analysis of the microstructure and composition of diffusion composite layers obtained as a result of thermal-chemical treatment (TCT) is presented and the distribution of microhardness in these layers is studied depending on the formed borides and carbides. The influence of processing temperature modes of on the parameters of roughness was experimentally established and the wear resistance characteristics of the processed surfaces of the investigated materials were determined.

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