Anastasiia Zelena Development of Inserts Processing and Casting Technology from X34Cr20Mo10Si10V (4H5MFS) Steel SCIENTIFIC SUPERVISOR:Ph.D. assoc. prof.

Anastasiia Zelena

Development of Inserts Processing and Casting Technology from X34Cr20Mo10Si10V (4H5MFS) Steel

SCIENTIFIC SUPERVISOR: Ph.D. assoc. prof.O. Uzlov

LANGUAGE SUPERVISOR: lect. M.Nedogibchenko

Purpose of the work: Explore the possibility of obtaining high-quality product from recycled material of X34Cr20Mo10SiV ( 4H5MFS) steel

Tasks of research :1. To develop the most rational scheme of melting contaminated packed cutting2. To find the best strategy of the steel casting3. To examine the quality of finished product’s material after the final heat treatment

PRYDNIPROVS’KA STATE ACADEMY OF CIVIL ENGINEERING AND ARCHITECTURE

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Hard working conditions require high range of properties of steels which the stamps are made of:

1. Heat resistance. 2. Necessary impact strength. 3. High crazing resistance. 4. Hardenability. 5. Oxidation resistance.

The process of mechanical treatment develops thousands of tons of cutting from steel X34Cr20Mo10SiV (4H5MFS). A problem of its usage is very urgent in Ukraine, which possesses limited sources of raw materials.

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Table 1 Chemical composition of researched material. Wt, %

C Si Mn Ni S P Cr Mo V Cu

0.34 0.92 0.4 to   0.35 to   0.03 to   0.03 5.3 1.4 0.35 to   0.3

Material and methods of researches

Fig.1. Neophot 2.1

The investigation of microstructures were held with the help of light microscopes Neophot 2 and Neophot 2.1

Measurements of microhardness were held by Vickers method in accordance with GOST 9013-59 on PMT-3 device at loading of 5 kg. Measurements of hardness were held by Rockwell method on ТР-003

Fig. 2. PMT-3

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Fig. 3 Typical nonmetallic inclusions in X34Cr20Mo10SiV (4H5MFS) steel structure, A) obtained by industrial smelting, B) obtained by centrifugal casting

A) х1000

Quality estimation of product’s material from steel X34Cr20Mo10SiV manufactured on the metallurgical enterprise and made by centrifugal casting.

B) х1000

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Microhardness of dark areas is 423 HV, microhardness of light areas is 500 HV

А) х25 B) х25

Fig.4 Structural heterogeneity A) in the industrial steel X34Cr20Mo10SiV (4H5MFS); B) in centrifugal cast steel

Microhardness of dark areas is 428 HV, microhardness of light areas is 478 HV

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А) х1000 B) х1000

Fig. 5 Microstructure of A) industrial steel X34Cr20Mo10SiV (4H5MFS) and B) centrifugal smelt steel after standard heat treatment.

Observation of hardness over the cross- section of a product in two perpendicular directions have not revealed an essential difference in hardness of surface and deep layers : A) 43-45 HRC; B) 45-47 HRC

Fig. 6 Inclusions of sulfides in X34Cr20Mo10SiV (4H5MFS) steel

structure obtained by centrifugal casting

А) х400 B) х1000

Occurrence of these inclusions can be explained by pollution of initial charge (packed cutting) by various chemical compounds containing sulfur.

In the industrial steel any sulfides have not been revealed

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Cost efficiencyCost standards and value of alloying materials

Alloying material

Price excluding VAT, UAH/kg

X34Cr20Mo10SiV (4H5MFS)

Alloying element cost, kg/ton

Price, UAH / ton

Ferro-Mn (78% Mn)

14,4-16 5,69 81,9

Ferro-Si (25% Si)

8-9,6 73,6 588,8

Ferro-V (75% V)

304-496 5,8 1763,2

Ferro-Cr (87% Cr)

16-25,6 341,9 5470,4

Cu 88-115,2 10,7 941,6

Ferro-Mo (60% Mo)

400-464 29,16 11664

Total (excluding VAT), UAH

466,85 20509,9

P = R – C

P - profit for 1 ton of steel, UAHR - revenues from sales, UAHC - steel manufacturing cost, UAH P = 36330-20509,9 = 15820,1 UAH

Pt = (P - Сs) * Vс

Cs - steel smelting cost, UAH Vc - annual cutting volume, tonPt – total profit, UAH

Pt = (15820,1-6000) * 17,5 = 171851,75 UAH

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1. Comparative estimation of structural characteristics deformed and centrifugal cast metal allows to draw a preliminary conclusion on their similarity.

2. Experimental metal tends to improvement of morphology of nonmetallic inclusions, structural homogeneity and microhardness, but concedes on austenite primary grain size and on sulfides presence in structure.

3. The distinction of structural characteristics cannot essentially affect durability of products, which should be estimated by results of operational tests in conditions of manufacture.

4. Advanced material not only does not concede on the properties primary, but also in some cases exceeds them.

5. The economy of Ukraine requires resolute actions on usage and processing of secondary raw material in manufacture with a view of economy and rational utilizing resources of the country.

6. Usage of the second raw material as a charge for stamp instrument producing will bring annual income around 170000 UAH.

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THANK YOU FOR YOUR ATTENTION