Направленная кристаллизация образцов из 316 методом прямого лазерного нанесения
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«Çàâîäcêàÿ ëàáîpàòîpèÿ. Äèàãíîcòèêà ìàòåpèàëîâ». 2018. Òîì 84. ¹ 1(I) 29 Èññëåäîâàíèå ñòðóêòóðû è ñâîéñòâ Structure and properties research Ôèçè÷åñêèå ìåòîäû èññëåäîâàíèÿ è êîíòðîëÿ Physical methods of research and monitoring DOI: 10.26896/1028-6861-2018-84-1-I-29-35 ÓÄÊ (UDC) 621.9.048.7 ÍÀÏÐÀÂËÅÍÍÀß ÊÐÈÑÒÀËËÈÇÀÖÈß ÎÁÐÀÇÖΠÈÇ ÍÅÐÆÀÂÅÞÙÅÉ ÑÒÀËÈ 316L ÌÅÒÎÄÎÌ ÏÐßÌÎÃÎ ËÀÇÅÐÍÎÃÎ ÍÀÍÅÑÅÍÈß ÌÅÒÀËËÀ1 © Àíäðåé Èãîðåâè÷ Ãîðóíîâ Êàçàíñêèé íàöèîíàëüíûé èññëåäîâàòåëüñêèé òåõíè÷åñêèé óíèâåðñèòåò èì. À. Í. Òóïîëåâà — ÊÀÈ, ã. Êàçàíü, Ðîññèÿ; e-mail: gorunow.andrej@yandex.ru Ñòàòüÿ ïîñòóïèëà 23 ìàÿ 2017 ã. Ïîêàçàíû ïðåèìóùåñòâà ìåòîäà ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ ìåòàëëà, îáåñïå÷èâàþùåãî íàïðàâëåííóþ êðèñòàëëèçàöèþ îáðàçöîâ èç íåðæàâåþùåé ñòàëè 316L. Óñòàíîâëåíî, ÷òî ìåòîä îòêðûâàåò øèðîêèå âîçìîæíîñòè äëÿ ïîëó÷åíèÿ ìîíîêðèñòàëëè÷åñêèõ ñòðóêòóð ïóòåì íàïðàâëåííîé êðèñòàëëèçàöèè íàïëàâëÿåìîãî ìåòàëëà. Ñòðóêòóðà ìåòàëëà ïîëó÷àåìûõ îáðàçöîâ ïðåäñòàâëåíà äåíäðèòíûìè êðèñòàëëàìè, îðèåíòèðîâàííûìè â íàïðàâëåíèè òåïëîâîãî öåíòðà.  ïîïåðå÷íîì ñå÷åíèè ñòðóêòóðà, îáðàçîâàííàÿ îñÿìè êðèñòàëëîâ ïåðâîãî ïîðÿäêà, èìååò âèä ñîò. Òîëùèíà íàíîñèìîãî ñëîÿ (200 ìêì) â öåíòðàëüíîé ÷àñòè îáðàçöà íå ïðåïÿòñòâóåò ðàçâèòèþ äåíäðèòíîé ñòðóêòóðû è ñïîñîáñòâóåò ôîðìèðîâàíèþ ìîíîêðèñòàëëè÷åñêèõ ñòðóêòóð (ñ îòñóòñòâèåì ïîð è òðåùèí). Îòìå÷åíî, ÷òî íàïðàâëåíèå ðîñòà äåíäðèòíûì êðèñòàëëàì çàäàåò òåïëîâîé öåíòð, îïðåäåëÿåìûé ïîëîæåíèåì ëàçåðíîãî ïÿòíà. Ïðåäñòàâëåíà ìåòîäèêà ïîëó÷åíèÿ èçäåëèé èç íåðæàâåþùåé ñòàëè ñ èñïîëüçîâàíèåì òåõíîëîãèè ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ ïî ðàçðàáîòàííîìó àëãîðèòìó, ïîçâîëÿþùåìó êîíòðîëèðîâàòü ïåðåìåùåíèå ðîáîòèçèðîâàííîãî êîìïëåêñà è îáðàçöà, âêëþ÷åíèå ëàçåðà è ïîäà÷ó ãàçîïîðîøêîâîé ñìåñè. Ïîêàçàíû âîçìîæíîñòè îïðåäåëåíèÿ óãëà íàêëîíà äåíäðèòíûõ êðèñòàëëîâ â ìåòàëëå îòíîñèòåëüíî îñè ñèììåòðèè îáðàçöà ñ ïîìîùüþ ìåòàëëîãðàôè÷åñêîãî ïðîãðàììíîãî êîìïëåêñà àíàëèçà öèôðîâûõ èçîáðàæåíèé ìèêðîñòðóêòóð, à òàêæå êîíòðîëÿ êà÷åñòâà ïîëó÷àåìûõ èçäåëèé ñ ïîìîùüþ ðåíòãåíîâñêîé òîìîãðàôèè, ïîäáîðà ïàðàìåòðîâ ëàçåðíîãî ïÿòíà íà ïîâåðõíîñòè ïîäëîæêè ïðè âûñîêîñêîðîñòíîé ñúåìêå, îöåíêè ôàçîâîãî ñîñòàâà íàïëàâëåííîãî ìåòàëëà ìåòîäîì ðåíòãåíîñòðóêòóðíîãî àíàëèçà. Ïðè ýòîì øåðîõîâàòîñòü îáðàçöîâ, îïðåäåëÿåìóþ ðàçìåðîì ïîðîøêîâûõ ÷àñòèö, ìîæíî óñòðàíèòü ìåõàíè÷åñêîé îáðàáîòêîé. Êëþ÷åâûå ñëîâà: àääèòèâíîå ïðîèçâîäñòâî; ëàçåðíàÿ íàïëàâêà; íåðæàâåþùàÿ ñòàëü; ìèêðîñòðóêòóðà; òâåðäîñòü. DIRECTIONAL CRYSTALLIZATION OF 316L STAINLESS STEEL SPECIMENS BY DIRECT LASER CLADDING © Andrey I. Gorunov Kazan National Research Technical University, Kazan, Russia: e-mail: gorunow.andrej@yandex.ru Submitted May 23, 2017. Advantages of direct laser cladding of metal consisting in the possibility of directional crystallization of 316L stainless steel samples are shown. Direct laser cladding of metal offers exciting possibilities for 1 Ðàáîòà âûïîëíåíà â ðàìêàõ ãîñóäàðñòâåííîãî çàäàíèÿ Ìèíîáðíàóêè ÐÔ (çàäàíèå ¹ 9.3236.2017/4.6). 30 «Çàâîäcêàÿ ëàáîpàòîpèÿ. Äèàãíîcòèêà ìàòåpèàëîâ». 2018. Òîì 84. ¹ 1(I) production of single crystal structures by directional crystallization of the deposited metal. The growth direction of dendritic crystals is driven by the thermal center determined by the position of the laser spot. We present a technique of manufacturing stainless steel products by direct laser deposition using the developed algorithm which allowed us to connect the movement of the robotic cell and turntable with a sample, laser switching and feeding of the gas powder mixture. The possibility of x-ray tomographic quality control of the obtained products, determination of the parameters of the laser spot on the substrate surface using high-speed photography, estimation of the phase composition of the deposited metal using x-ray diffraction analysis is demonstrated. The structure of obtained metal samples is represented by dendritic crystals oriented in the direction of the thermal center. The sample structure in the sample cross section is represented in the form of a honeycomb formed by the first order axes of dendritic crystals. It is shown that 200-ìm thickness of the deposited layer in the central part of the sample does not interfere with the development of the dendritic structure and promotes the possibility of obtaining single-crystal structures free of pores and cracks. The possibility of estimating the inclination angle of dendritic crystals in the metal relative to the symmetry axis of the sample using a metallographic software package for analysis of digital images of the microstructures is shown. It is demonstrated that the roughness of the obtained samples is determined by the size of the powder particles and can be eliminated by the mechanical treatment. Keywords: additive manufacturing; laser cladding; stainless steel; microstructure; hardness. Èçäåëèÿ, ïîëó÷àåìûå àääèòèâíûì ìåòîäîì, àêòèâíî âíåäðÿþòñÿ â ñåðèéíîå ïðîèçâîäñòâî, íàïðèìåð, â òàêèõ îòðàñëÿõ, êàê ìàøèíî- è ñàìîëåòîñòðîåíèå [1, 2]. Îäíàêî, ïðèîáðåòàÿ äîðîãîñòîÿùåå îáîðóäîâàíèå äëÿ 3D ïå÷àòè, ïðîèçâîäèòåëè ñòàëêèâàþòñÿ ñ òåì, ÷òî ñòîèìîñòü ðàñõîäíûõ ìàòåðèàëîâ ìîæåò äîñòèãàòü òðåòè îò ñòîèìîñòè ïðèáîðà, à òåõíîëîãèÿ äëÿ èçãîòîâëåíèÿ äàæå ïðîñòîé äåòàëè ìîæåò â äåñÿòêè ðàç ïðåâûøàòü ñòîèìîñòü ñàìîãî ïðèîáðåòàåìîãî îáîðóäîâàíèÿ.  íàñòîÿùåå âðåìÿ àêòèâíî ðàçðàáàòûâàþòñÿ íîâûå ìåòîäû, àëãîðèòìû è óñòðîéñòâà äëÿ àääèòèâíîãî ïðîèçâîäñòâà ïîðîøêîâûõ ìàòåðèàëîâ è èçäåëèé, íå óñòóïàþùèõ ïî ñêîðîñòè èçãîòîâëåíèÿ è êà÷åñòâó çàðóáåæíûì àíàëîãàì. Îáúÿâëåííûå íà ãîñóäàðñòâåííîì óðîâíå ñòðàòåãè÷åñêèå íàïðàâëåíèÿ ðàçâèòèÿ ìàòåðèàëîâ âêëþ÷àþò ðàçðàáîòêó àääèòèâíûõ òåõíîëîãèé ïîëó÷åíèÿ äåòàëåé, ìîíîêðèñòàëëè÷åñêèõ è åñòåñòâåííûõ êîìïîçèòîâ, êîððîçèîííî-ñòîéêèõ ñâàðèâàåìûõ ñïëàâîâ è ñòàëåé [3]. Îäíî èç íàïðàâëåíèé, îòíîñÿùååñÿ ê àääèòèâíûì òåõíîëîãèÿì, — ïðÿìîå ëàçåðíîå íàíåñåíèå ìåòàëëà [4 – 9]. Ìîùíûé ëàçåðíûé ëó÷ ðàçîãðåâàåò ïîðîøêîâûé ìàòåðèàë, ïîäàâàåìûé â çîíó íàíåñåíèÿ ñ ïîìîùüþ êîàêñèàëüíîãî ñîïëà. Ìàòåðèàë íàíîñÿò â ðàñïëàâëåííîì ñîñòîÿíèè, ñëîé çà ñëîåì. Ìåòîä îáåñïå÷èâàåò ðÿä ïðåèìóùåñòâ ïî ñðàâíåíèþ ñ òðàäèöèîííûìè ñïîñîáàìè ëèòüÿ è îáðàáîòêè ìåòàëëîâ äàâëåíèåì: áîëåå âûñîêóþ ñêîðîñòü èçãîòîâëåíèÿ èçäåëèé, îòñóòñòâèå òðåáîâàíèé ê òåõíîëîãè÷åñêîé îñíàñòêå, âîçìîæíîñòü èçãîòîâëåíèÿ ñëîæíûõ ôîðì [10 – 14]. Íåñìîòðÿ íà òî, ÷òî ðåçóëüòàòû îòäåëüíûõ èññëåäîâàíèé ìèêðîñòðóêòóðíûõ õàðàêòåðèñòèê è ìèêðîòâåðäîñòè îáðàçöîâ èç íåðæàâåþùèõ ñòàëåé, ñôîðìèðîâàííûõ ìåòîäîì ëàçåðíîé íàïëàâêè, õîðîøî èçâåñòíû [15], ïîòåíöèàë òåõíîëîãèè ïðèìåíèòåëüíî ê àääèòèâíîìó ïðîèçâîäñòâó äî êîíöà íå ðàñêðûò. Âîïðîñû, ñâÿçàííûå ñ ôîðìèðîâàíèåì ìîíîêðèñòàëëè÷åñêèõ ñòðóêòóð â ìíîãîñëîéíûõ èçäåëèÿõ, à òàêæå àëãîðèòì èõ ïîëó÷åíèÿ ìåòîäîì ïðÿìîãî ëàçåðíîãî âûðàùèâàíèÿ èçó÷åíû äîñòàòî÷íî ñëàáî. Öåëü ðàáîòû — èññëåäîâàíèå çàêîíîìåðíîñòè ôîðìèðîâàíèÿ ñòðóêòóðû è ñâîéñòâ èçäåëèé èç íåðæàâåþùåé ñòàëè, ïîëó÷åííûõ ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ, è ðàçðàáîòêà ðåêîìåíäàöèé ïî âîçìîæíîìó èñïîëüçîâàíèþ ìåòîäà äëÿ ñîçäàíèÿ ìîíîêðèñòàëëè÷åñêèõ ñòðóêòóð. Äëÿ ïîëó÷åíèÿ èçäåëèé ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ èñïîëüçîâàëè êîàêñèàëüíîå ñîïëî, êîòîðîå ïåðåìåùàëè ñ ïîìîùüþ ðîáîòà. Äëÿ îïëàâëåíèÿ ïîðîøêîâîãî ìàòåðèàëà (íåðæàâåþùàÿ ñòàëü ìàðêè 316Ä, ðàçìåð ÷àñòèö — 45 – 100 ìêì) ïðèìåíÿëè èòòåðáèåâûé âîëîêîííûé ëàçåð (äëèíà âîëíû — 1070 íì).  êà÷åñòâå ãàçà äëÿ òðàíñïîðòèðîâêè ïîðîøêîâîãî ìàòåðèàëà èñïîëüçîâàëè àðãîí (ðàñõîä — 3 ë/ìèí, ðàñõîä äîïîëíèòåëüíîãî ãàçà äëÿ ôîðìèðîâàíèÿ ãàçîïîðîøêîâîãî ïîòîêà — 5 ë/ìèí). Ëàçåðíûé ëó÷ ôîêóñèðîâàëè íà ïîâåðõíîñòè ïîäëîæêè èç ñðåäíåóãëåðîäèñòîé ñòàëè. Ïðè ýòîì ðàáî÷åå ðàññòîÿíèå ìåæäó ñîïëîì è ïîäëîæêîé îñòàâàëîñü ïîñòîÿííûì è ñîñòàâëÿëî 5 ìì. Ðàñõîä ïîðîøêîâîãî ìàòåðèàëà ñîñòàâëÿë 0,05 ã/ñ. Õèìè÷åñêèé ñîñòàâ èññëåäóåìîé ñòàëè 316L ñëåäóþùèé, % ìàññ.: 18 Cr; 3 Mo; 14 Ni; 0,03 C; 2 Mn; 0,75 Si; 0,045 P; 0,03 S (îñíîâà — Fe). Ìèêðîòâåðäîñòü èçìåðÿëè ñ ïîìîùüþ àâòîìàòèçèðîâàííîãî òâåðäîìåðà Tukon 2500. Äëÿ ôîðìèðîâàíèÿ ïîëÿ ðàñïðåäåëåíèÿ ìèêðîòâåðäîñòè ïîñëå àâòîìàòè÷åñêîãî íàíåñåíèÿ îòïå÷àòêîâ íà ïîâåðõíîñòü øëèôà èñïîëüçîâàëè êîìïüþòåðíóþ ïðîãðàììó Tixomet. Èçìåðåíèÿ øåðîõîâàòîñòè è ïðîôèëÿ ïîâåðõíîñòè ïîêðûòèÿ âûïîëíÿëè ñ ïîìîùüþ ïðîôèëîãðàôà-ïðîôèëîìåòðà «Àáðèñ-ÏÌ7». 31 Âûñîòà ïðîôèëÿ, ìêì «Çàâîäcêàÿ ëàáîpàòîpèÿ. Äèàãíîcòèêà ìàòåpèàëîâ». 2018. Òîì 84. ¹ 1(I) Äëèíà ó÷àñòêà ñêàíèðîâàíèÿ êàíòèëåâåðîì, ìì à á â Ðèñ. 1. Êîìïüþòåðíàÿ ìîäåëü (à), ñîåäèíèòåëüíàÿ ìóôòà (á ), ïîëó÷åííàÿ ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ, è öèëèíäðè÷åñêàÿ îáîëî÷êà — îáðàçåö äëÿ èññëåäîâàíèÿ (â) Îáðàçöû ïåðåä àíàëèçîì ìàêðî- è ìèêðîñòðóêòóðû øëèôîâàëè àëìàçíûìè øëèôîâàëüíûìè äèñêàìè (120, 220 è 500 grit), çàòåì ïîëèðîâàëè ñ èñïîëüçîâàíèåì àëìàçíûõ ñóñïåíçèé (9 è 3 ìêì). Òðàâëåíèå îñóùåñòâëÿëè â ïîäãîòîâëåííîì ðåàêòèâå àçîòíîé êèñëîòû. Äëÿ âûÿâëåíèÿ â îáðàçöàõ ïîð è òðåùèí ïðèìåíÿëè ðåíòãåíîâñêèé êîìïüþòåðíûé òîìîãðàô Õ5000 ñåðèè XView™. Ìèêðîñòðóêòóðó îáðàçöîâ èññëåäîâàëè ñ ïîìîùüþ îïòè÷åñêîãî ìèêðîñêîïà Axio Observer Dlm Carl Zeiss. Ðåíòãåíîôàçîâûé àíàëèç ïðîâîäèëè ñ ïîìîùüþ ìíîãîôóíêöèîíàëüíîãî äèôðàêòîìåòðà Rigaku SmartLab. Äèôðàêòîãðàììû ðåãèñòðèðîâàëè â ãåîìåòðèè Áðýããà – Áðåíòàíî ïðè óñëîâèè, ÷òî ùåëè íà ïåðâè÷íîì ïó÷êå ñîñòàâëÿëè 10 ìì (èíòåðâàë ñêàíèðîâàíèÿ — 10 – 90°, øàã ñêàíèðîâàíèÿ — 0,02°, âðåìÿ ñúåìêè â òî÷êå — 5 ñ). Âèäåîðåãèñòðàöèþ ïðîöåññà ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ îñóùåñòâëÿëè ñ ïîìîùüþ ñêîðîñòíîé êàìåðû NAC HX-4 Memrecam (÷àñòîòà êàäðîâ ïðè ñúåìêå — 2000 êàäðîâ/ñ). Ïðÿìîå ëàçåðíîå íàíåñåíèå îñóùåñòâëÿëè â ðåæèìå, îáåñïå÷èâàþùåì ñòàáèëüíîñòü âûðàùèâàíèÿ öèëèíäðè÷åñêîé îáîëî÷êè (îáðàçöà) — îñíîâû äëÿ êîíå÷íîãî èçäåëèÿ (ìóôòû). Ñòàáèëüíîñòü ðåæèìà äîñòèãàëàñü òåì, ÷òî íàïëàâî÷íîå ñîïëî ïîäíèìàëè ïðè êàæäîì ïîñëåäóþùåì íàíåñåíèè ñ øàãîì, ñîîòâåòñòâóþùèì âûñîòå îäíîãî ñëîÿ. Ïî àëãîðèòìó, çàäàâàåìîìó ïðîãðàììîé [16], óïðàâëÿëè ìàíèïóëÿöèÿìè ðîáîòà, óäåðæèâàþùåãî êîàêñèàëüíîå ñîïëî, ïîäà÷åé ãàçîïîðîøêîâîé ñìåñè, çàùèòíîãî ãàçà è âêëþ÷åíèåì ëàçåðà. Äëÿ ïîëó÷åíèÿ èçäåëèÿ (ñîåäèíèòåëüíîé ìóôòû) èç íåðæàâåþùåé ñòàëè 316L ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ ìàòåðèàëà (ðèñ. 1) òðóá÷àòûå çàãîòîâêè (îáðàçöû) ìåõàíè÷åñêè îáðàáàòûâàëè è ïîëèðîâàëè (òîëùèíà ñòåíêè èçäåëèÿ ñîñòàâëÿëà 1 – 1,2 ìì). Íà ðèñ. 2 ïðåäñòàâëåíû ïðîôèëîãðàììû âíåøíåé è âíóòðåííåé ïîâåðõíîñòåé çàãîòîâ- Ðèñ. 2. Ïðîôèëîãðàììû âíóòðåííåé (ñïëîøíàÿ ëèíèÿ) è íàðóæíîé (ïóíêòèð) ïîâåðõíîñòåé öèëèíäðè÷åñêîé îáîëî÷êè à á â ã ä å æ ç Ðèñ. 3. Êîìïüþòåðíàÿ ìîäåëü (à – ã) è ðåíòãåíîâñêèå ñíèìêè öèëèíäðè÷åñêèõ îáðàçöîâ (ä – ç ) â ðàçëè÷íûõ ñå÷åíèÿõ êè, âûðàùåííîé ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ. Óñòàíîâèëè, ÷òî øåðîõîâàòîñòè âíóòðåííèõ è íàðóæíûõ ñëîåâ áëèçêè (ðàçáðîñ ìåæäó ìàêñèìàëüíûì è ìèíèìàëüíûì çíà÷åíèåì íå ïðåâûøàåò 200 ìêì) [21] è îïðåäåëÿþòñÿ â îñíîâíîì ðàçìåðîì ïîðîøêîâûõ ÷àñòèö, ò.å. êà÷åñòâî ïîëó÷àåìîé ïîâåðõíîñòè öèëèíäðè÷åñêèõ çàãîòîâîê (îáðàçöîâ) äîñòàòî÷íî íèçêîå. Íà ðèñ. 3 ïðåäñòàâëåíû èçîáðàæåíèÿ çàãîòîâîê â ðàçëè÷íûõ ñå÷åíèÿõ, ïîëó÷åííûå íà ðåíòãåíîâñêîì òîìîãðàôå. Íåäîñòàòî÷íàÿ çàùèòà â ãàçîâîé ñðåäå ïðè ðàñïëàâëåíèè ïîðîøêîâîãî ìàòåðèàëà ïðèâîäèò ê ôîðìèðîâàíèþ âûñîêîé ïîðèñòîñòè. Ïðè äëèòåëüíîì ïåðåãðåâå íàïëàâëÿåìîãî ìåòàëëà (ñëó÷àåòñÿ ïðè ïðåâûøåíèè ìîùíîñòè ëàçåðíîãî èçëó÷åíèÿ 2 êÂò) â ïîïåðå÷íîì ñå÷åíèè ôèêñèðîâàëè îáðàçîâàíèå êðóïíûõ ïîð (ñì. ðèñ. 3, ã, ç ). Èç-çà íàðóøåíèÿ ñòàáèëüíîñòè ãàçîïîðîøêîâîãî ïîòîêà íàáëþäàëè ñìåùåíèå îáðàçöà âñëåäñòâèå ðàñòåêàíèÿ ïî ïîâåðõíîñòè ïîäëîæêè íàïëàâëÿåìîãî ìåòàëëà èëè åãî âñêèïàíèÿ. Íà ðèñ. 4 ïðåäñòàâëåíà ìèêðîñòðóêòóðà îáðàçöà â ïðîäîëüíîì è ïîïåðå÷íîì ñå÷åíèÿõ. Âèäíî, ÷òî â ïðîäîëüíîì ñå÷åíèè ïðîèçîøëî ôîðìèðîâàíèå îðèåíòèðîâàííîé äåíäðèòíîé ñòðóêòóðû. Çàìåòèì, ÷òî ðîñò äåíäðèòíûõ êðè- 32 «Çàâîäcêàÿ ëàáîpàòîpèÿ. Äèàãíîcòèêà ìàòåpèàëîâ». 2018. Òîì 84. ¹ 1(I) à â 100 ìêì 200 ìêì á ã 20 ìêì 20 ìêì Ðèñ. 4. Ìèêðîñòðóêòóðà â ïðîäîëüíîì (à, á ) è ïîïåðå÷íîì (â, ã ) ñå÷åíèÿõ îáðàçöà èç ñòàëè 316L, ïîëó÷åííîãî ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ ñòàëëîâ (ñì. ðèñ. 4, à) íå îñòàíàâëèâàåòñÿ íà ãðàíèöå ñëîåâ. Äëèíà îñè ïåðâîãî ïîðÿäêà ñîñòàâëÿåò ~500 ìêì ïðè óñëîâèè, ÷òî âûñîòà êàæäîãî íàíåñåííîãî ñëîÿ — 100 – 150 ìêì.  ïîïåðå÷íîì ñå÷åíèè äåíäðèòíûå êðèñòàëëû ïðåäñòàâëåíû êàê âûñîêîäèñïåðñíàÿ ÿ÷åèñòàÿ (ñîòîâàÿ) ñòðóêòóðà, à îñè ïåðâîãî ïîðÿäêà íàïðàâëåíû ïåðïåíäèêóëÿðíî ïëîñêîñòè ðåçà. Ïðè ýòîì ãðàíèöû çåðåí íå îáíàðóæèâàþòñÿ è ñðåäíèé äèàìåòð êðèñòàëëîâ ñîñòàâëÿåò 5 – 15 ìêì. Ëàçåðíûé ëó÷ ðàçîãðåâàåò ïîðîøêîâûé ìàòåðèàë âïëîòü äî åãî ïîëíîãî ðàñïëàâëåíèÿ. Ñêîðîñòü æå êðèñòàëëèçàöèè íàñòîëüêî âûñîêà, ÷òî îñè âòîðîãî è òðåòüåãî ïîðÿäêîâ íå óñïåâàþò ðàçâèòüñÿ. Ïðè ñïåêàíèè ïîðîøêîâîãî ìàòåðèàëà 316L ìåòîäîì ñåëåêòèâíîãî ëàçåðíîãî ïëàâëåíèÿ îáðàçóþùàÿñÿ â ìåòàëëå çåðíåííàÿ ñòðóêòóðà [17] äîëæíà ñïîñîáñòâîâàòü îñòàíîâêå äèñëîêàöèé â ïðîöåññå ïëàñòè÷åñêîé äåôîðìàöèè. Ðàçëè÷èå â ñòðóêòóðå äëÿ îäíîãî è òîãî æå ìàòåðèàëà (316L), ïîëó÷åííîãî ðîäñòâåííûìè ìåòîäàìè ñåëåêòèâíîãî ëàçåðíîãî ïëàâëåíèÿ è ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ, ìîæíî îáúÿñíèòü ðàçíîñòüþ â ïëîòíîñòè ìîùíîñòè ëàçåðíîãî èçëó÷åíèÿ, ôîêóñèðóåìîãî íà îáðàáàòûâàåìîé ïîâåðõíîñòè, ñòåïåíè ðàñïëàâëåíèÿ ïîðîøêîâîãî ìàòåðèàëà, ñêîðîñòè êðèñòàëëèçàöèè ðàñïëàâà, ñòåïåíè çàùèòû âàííû ðàñïëàâà â ãàçîâîé ñðåäå è äð. Íà ðèñ. 5 ïðèâåäåíû èçîáðàæåíèÿ ëàçåðíîãî ïÿòíà, ïîëó÷åííûå ñ ïîìîùüþ âûñîêîñêîðîñòíîé ñúåìêè â ïðîöåññå ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ. Ïîñëå âêëþ÷åíèÿ ëàçåðà è íà÷àëà äâèæåíèÿ ñîïëà ïðîèñõîäèò ôîðìèðîâàíèå òàê íàçûâàåìîãî «õâîñòèêà», òÿíóùåãîñÿ âñëåä çà ïÿòíîì. Ñêîðîñòü ïåðåìåùåíèÿ ëàçåðíîãî ïÿòíà âûáèðàëè òàêèì îáðàçîì, ÷òîáû ìèíèìèçèðîâàòü íàðàñòàíèå «õâîñòèêà». Ýòîãî äîñòèãàëè âûñîêîé ñêîðîñòüþ äâèæåíèÿ ñîïëà. Íèçêàÿ ñêîðîñòü ïåðåìåùåíèÿ ëàçåðà ñîçäàåò óñëîâèÿ äëÿ äëèòåëüíîãî íàõîæäåíèÿ íàïëàâëÿåìîãî ìåòàëëà âûøå òåìïåðàòóðû ïëàâëåíèÿ, ÷òî âåäåò ê åãî îêèñëåíèþ è èñêðèâëåíèþ îñåé äåíäðèòíûõ êðèñòàëëîâ. Ïî ïîëó÷åííûì äèôðàêòîãðàììàì (ðèñ. 6) âèäíî, ÷òî â îáðàçöå ïðèñóòñòâóåò ôàçà ã-Fe ñ ïðîñòðàíñòâåííîé ãðóïïîé Fm-3m è ïàðàìåòðàìè ðåøåòêè: a = 3,6009, b = 3,6009 è c = 3,6009 Å. «Çàâîäcêàÿ ëàáîpàòîpèÿ. Äèàãíîcòèêà ìàòåpèàëîâ». 2018. Òîì 84. ¹ 1(I) 33 à á â ã Ðèñ. 5. Ôîðìà ëàçåðíîãî ïÿòíà, ïîëó÷åííîãî ñ ïîìîùüþ âûñîêîñêîðîñòíîé ñúåìêè â èíòåðâàëå 0,5 (à), 1 (á ), 2 (â ) è 4 ñ (ã ) ïîñëå âêëþ÷åíèÿ ëàçåðà è äâèæåíèÿ ñîïëà Äîïîëíèòåëüíûõ ôàç, â òîì ÷èñëå òèïà MeO è MeC, íå âûÿâëåíî ëèáî ïðîöåíò èõ ñîäåðæàíèÿ íåçíà÷èòåëåí. Èçâåñòíî, ÷òî ðàçìåð äåíäðèòíûõ êðèñòàëëîâ îãðàíè÷èâàåòñÿ òîëùèíîé ñëîÿ ìåòàëëà â ïðîöåññå ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ [18]. Ýòî îáúÿñíÿåòñÿ íàêîïëåíèåì âêëþ÷åíèé, îáðàçóþùèõ öåíòðû êðèñòàëëèçàöèè, íà ãðàíèöàõ ñëîåâ, ïðåïÿòñòâóþùèõ ïðîäâèæåíèþ ðàíåå ñôîðìèðîâàííûõ êðèñòàëëîâ. Ïðåèìóùåñòâî ìåòîäà ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ — îáäóâ çîíû ëàçåðíîé íàïëàâêè çàùèòíûì ãàçîì. Ýòî ïîçâîëÿåò èñêëþ÷èòü, íàïðèìåð, âëèÿíèå âûäåëÿþùèõñÿ â ïðîöåññå íàïëàâêè ïàðîâ îêñèäîâ æåëåçà [19].  ñëó÷àå ñåëåêòèâíîãî ëàçåðíîãî ïëàâëåíèÿ, êîòîðîå ïðîâîäÿò â çàêðûòîé êàìåðå 3D-ïðèíòåðà ïóòåì ñïåêàíèÿ ëàçåðîì ïîðîøêà, ïðåäâàðèòåëüíî ðàâíîìåðíî ðàñïðåäåëåííîãî ïî ïîâåðõíîñòè ïîäëîæêè, íàïðîòèâ, äîïîëíèòåëüíûé îáäóâ çîíû âîçäåéñòâèÿ ëàçåðíîãî ïÿòíà íà ïîðîøîê íåâîçìîæåí, ïîñêîëüêó ýòî íàðóøàåò ñòàáèëüíîñòü ñïåêàíèÿ. Ñëåäîâàòåëüíî, äëÿ ïîëó÷åíèÿ ñòðóêòóðû, ñâîáîäíîé îò îêèñëîâ æåëåçà, íåîáõîäèìî âûðàùèâàíèå èçäåëèé ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ ñ èíòåíñèâíûì îáäóâîì âàííû ðàñïëàâà â ñðåäå çàùèòíîãî ãàçà. Íà ðèñ. 7 ïðåäñòàâëåíà ñòðóêòóðà îáðàçöîâ â ïðîäîëüíîì ñå÷åíèè. Âèäíî, ÷òî â öåíòðàëüíîé çîíå ïðåîáëàäàåò îðèåíòèðîâàííàÿ ñòðóêòóðà â íàïðàâëåíèè ïàðàëëåëüíîì âûðàùèâàíèþ îá- à Èíòåíñèâíîñòü à á 2è, ãðàä. Ðèñ. 6. Äèôðàêòîãðàììû îáðàçöà ñ äèôðàêöèîííûìè ïèêàìè ã-Fe: à — èñõîäíûé ïîðîøîê; á — íàïëàâëåííûé ìåòàëë ðàçöà, à íà êðàÿõ íàáëþäàåòñÿ îòêëîíåíèå äåíäðèòíûõ êðèñòàëëîâ íà óãîë 45° îòíîñèòåëüíî îñè, ïàðàëëåëüíîé íàïðàâëåíèþ âûðàùèâàíèÿ. Ïî öâåòîâîìó ïîëþ, îòðàæàþùåìó ðàñïðåäåëåíèå ìèêðîòâåðäîñòè, ðàññ÷èòàííîìó ïî èçìåðåííûì îòïå÷àòêàì àëìàçíîé ïèðàìèäêè (ðèñ. 8), âèäíî, ÷òî íà êðàÿõ îáðàçöà òâåðäîñòü íàïëàâëåííîãî ìåòàëëà ðàñòåò, à ïî ìåðå ïðîäâèæåíèÿ âãëóáü ñíèæàåòñÿ. Êðàåâîå ïîâûøåíèå ñâÿçàíî ñ òåì, ÷òî ñêîðîñòü îõëàæäåíèÿ íà ïîâåðõíîñòè îáðàçöà äîñòèãàåò ìàêñèìàëüíîãî çíà÷åíèÿ è íàðóæíûå ñëîè ìåòàëëà â áîëüøåé ñòåïåíè ïîäâåðæåíû âëèÿíèþ àòìîñôåðû âîçäóõà ïî ñðàâíåíèþ ñ öåíòðàëüíîé çîíîé. Ìîæíî ïðåäïîëîæèòü, ÷òî äîïîëíèòåëüíûé íàãðåâ, ïëàâíîå îõëàæäåíèå è çàùèòà âñåãî îáðàçöà â çàùèòíîé ãàçîâîé êàìåðå ïîçâîëÿò ãîìîãåíèçèðîâàòü ñâîéñòâà â åãî ñå÷åíèè. Äàëåå îöåíèâàëè ïîòåíöèàëüíûé ïðåäåë ïðî÷íîñòè îáðàçöîâ ïî èõ òâåðäîñòè [20]: óâ = á Ðèñ. 7. Ñòðóêòóðà ìåòàëëà îáðàçöà â ïðîäîëüíîì ñå÷åíèè (à), êîëè÷åñòâåííàÿ îöåíêà ñòðóêòóðíûõ ñîñòàâëÿþùèõ (á ) 34 «Çàâîäcêàÿ ëàáîpàòîpèÿ. Äèàãíîcòèêà ìàòåpèàëîâ». 2018. Òîì 84. ¹ 1(I) ËÈÒÅÐÀÒÓÐÀ à á Ðèñ. 8. Ðàñïðåäåëåíèå ìèêðîòâåðäîñòè â ïðîäîëüíîì ñå÷åíèè îáðàçöà (à) è çàìåðÿåìûõ îòïå÷àòêîâ (á ) (÷åðíûå ïóíêòèðíûå ëèíèè — ãðàíèöû ñëîåâ, ñèíèé è êðàñíûé îâàëû — îáëàñòè ïîíèæåííîé è ïîâûøåííîé òâåðäîñòè ñîîòâåòñòâåííî) = kHB (k — êîýôôèöèåíò, îïðåäåëÿåìûé ýêñïåðèìåíòàëüíî). Ñîãëàñíî ïîëó÷åííûì äàííûì ïî ðàñïðåäåëåíèþ òâåðäîñòè â ïðîäîëüíîì ñå÷åíèè îáðàçöà è ñ ó÷åòîì ìåõàíè÷åñêîé îáðàáîòêè â êîíå÷íîì èçäåëèè òâåðäîñòü ìåòàëëà ñîñòàâëÿåò ~322 HV0,1 (~315 HB ). Äëÿ èññëåäóåìîé ñòàëè k = 3,6 ïðè HB > 175. Ñëåäîâàòåëüíî, ðàñ÷åòíûé ïðåäåë ïðî÷íîñòè óâ = 1134 ÌÏà (íå óñòóïàåò ñâîéñòâàì íåðæàâåþùèõ ñòàëåé, èçãîòîâëåííûõ ïî òðàäèöèîííûì òåõíîëîãèÿì ïðîèçâîäñòâà). Òàêèì îáðàçîì, äëÿ ôîðìèðîâàíèÿ ñòîëá÷àòûõ ìîíîêðèñòàëëè÷åñêèõ ñòðóêòóð ïóòåì íàïðàâëåííîé êðèñòàëëèçàöèè íåîáõîäèì çíà÷èòåëüíûé òåìïåðàòóðíûé ãðàäèåíò, êîòîðûé ìîæíî çàäàòü ïîëîæåíèåì è ïàðàìåòðàìè ëàçåðíîãî ïÿòíà. Íàíåñåíèå ïåðâîãî ñëîÿ íà õîëîäíóþ ïîäëîæêó îïðåäåëÿåò ïîëîæåíèå è îðèåíòèðîâêó öåíòðîâ êðèñòàëëèçàöèè â ìåòàëëå. Ëàçåðíîå íàíåñåíèå êàæäîãî ñëåäóþùåãî ñëîÿ ñïîñîáñòâóåò ðîñòó ñôîðìèðîâàííûõ ðàíåå êðèñòàëëîâ (îíè áóäóò ïðîäîëæàòü ñâîé ðîñò ïî íàèáîëåå ýíåðãåòè÷åñêè âûãîäíîìó íàïðàâëåíèþ, ïðîáèâàÿñü îò ñëîÿ ê ñëîþ). Íàíîñèìûå ñëîè äîëæíû áûòü ïî âîçìîæíîñòè ìèíèìàëüíûìè, òàê êàê ñìåùåíèå òåïëîâîãî öåíòðà âåäåò ê èñêðèâëåíèþ êðèñòàëëîâ (â íàøåì ñëó÷àå òîëùèíà ñëîÿ íå ïðåâûøàëà 200 ìêì). Ïîñëå êàæäîãî íàíåñåíèÿ íåîáõîäèìà ïîëèðîâêà ñëîÿ. Ýòî ïîçâîëèò óñòðàíèòü ñ ïîâåðõíîñòè îáðàçóþùèéñÿ øëàê è îêñèäû, êîòîðûå ìîãóò îêàçàòü íåãàòèâíîå âëèÿíèå è ñîçäàòü äîïîëíèòåëüíûé áàðüåð äëÿ ôîðìèðîâàíèÿ ìîíîêðèñòàëëè÷åñêèõ ñòðóêòóð. Âìåñòå ñ òåì ñóùåñòâóåò ðèñê òîãî, ÷òî òóãîïëàâêèå îêñèäû îáðàçóþò áîëüøîå êîëè÷åñòâî öåíòðîâ êðèñòàëëèçàöèè. À ïîñêîëüêó íàðóæíûå ñëîè íà÷èíàþò êðèñòàëëèçîâàòüñÿ â ïåðâóþ î÷åðåäü, òî ìîæíî ïðåäïîëîæèòü, ÷òî ñêîðîñòü çàðîäûøåîáðàçîâàíèÿ ïðåâûñèò ñêîðîñòü ðîñòà êðèñòàëëîâ, â ðåçóëüòàòå ÷åãî ñôîðìèðóåòñÿ ïðîñëîéêà ðàçëè÷íî îðèåíòèðîâàííûõ êðèñòàëëîâ. 1. Êàáëîâ Å. Í. Àääèòèâíûå òåõíîëîãèè — äîìèíàíòà íàöèîíàëüíîé òåõíîëîãè÷åñêîé èíèöèàòèâû / Èíòåëëåêò & Òåõíîëîãèè. 2015. ¹ 2(11). Ñ. 52 – 55. 2. Ãðèãîðüåâ Ñ. Í., Ñìóðîâ È. Þ. Ïåðñïåêòèâû ðàçâèòèÿ èííîâàöèîííîãî àääèòèâíîãî ïðîèçâîäñòâà â Ðîññèè è çà ðóáåæîì / Èííîâàöèè. 2013. ¹ 10. Ñ. 76 – 82. 3. Êàáëîâ Å. Í. Ñòðàòåãè÷åñêèå íàïðàâëåíèÿ ðàçâèòèÿ ìàòåðèàëîâ è òåõíîëîãèé èõ ïåðåðàáîòêè íà ïåðèîä äî 2030 ãîäà / Àâèàöèîííûå ìàòåðèàëû è òåõíîëîãèè. 2012. ¹ 5. Ñ. 7 – 17. 4. Ãðèãîðüÿíö À. Ã., Øèãàíîâ È. Í., Ìèñþðîâ À. È. Òåõíîëîãè÷åñêèå ïðîöåññû ëàçåðíîé îáðàáîòêè. — Ì.: Èçä-âî ÌÃÒÓ èì. Í. Ý. Áàóìàíà, 2006. — 664 ñ. 5. Òóðè÷èí Ã., Çåìëÿêîâ Å., Ïîçäååâà Å., Òóîìèíåí ß. Òåõíîëîãè÷åñêèå âîçìîæíîñòè ëàçåðíîé íàïëàâêè ñ èñïîëüçîâàíèåì ìîùíûõ âîëîêîííûõ ëàçåðîâ / Ìåòàëëîâåäåíèå è òåðìè÷åñêàÿ îáðàáîòêà ìåòàëëîâ. 2012. ¹ 3. Ñ. 35 – 40. 6. Ãîðûíèí È. Â., Îðûùåíêî À. Ñ., Ìàëûøåâñêèé Â. À., Ôàðìàêîâñêèé Á. Â., Êóçíåöîâ Ï. À. Àääèòèâíûå òåõíîëîãèè íà áàçå êîìïîçèöèîííûõ íàíîìàòåðèàëîâ / Ìåòàëëîâåäåíèå è òåðìè÷åñêàÿ îáðàáîòêà ìåòàëëîâ. 2014. ¹ 10(712). Ñ. 4 – 8. 7. Sova A., Grigoriev S., Okunkova A., Smurov I. Cold spray deposition of 316L stainless steel coatings on aluminium surface with following laser post-treatment / Surface and Coatings Technology. 2013. Vol. 235. P. 283 – 289. 8. Ãîðóíîâ À. È. Ñîçäàíèå ïîêðûòèé è îáúåìíûõ èçäåëèé èç ìàòåðèàëà íà îñíîâå íèêåëÿ ìåòîäîì àääèòèâíîé ëàçåðíîé îáðàáîòêè / Ìåòàëëû. 2016. ¹ 1. Ñ. 101 – 105. 9. Gorunov A. I., Gilmutdinov A. Kh. Study of the effect of heat treatment on the structure and properties of the specimens obtained by the method of direct metal deposition / The International Journal of Advanced Manufacturing Technology. 2016. Vol. 86. Issue 9. P. 2567 – 2574. 10. Luo K., Jing X., Sheng J., Sun G., Yan Z., Lu J. Characterization and analyses on micro-hardness, residual stress and microstructure in laser cladding coating of 316L stainless steel subjected to massive LSP treatment / Journal of Alloys and Compounds. 2016. Vol. 673(15). P. 158 – 169. 11. Gorunov A. I., Gilmutdinov A. Kh. Investigation of coatings of austenitic steels produced by supersonic laser deposition / Optics & Laser Technology. 2017. Vol. 88. P. 157 – 160. 12. Peng G., Bin Z., Chuanzhen H., Huabing G. Study on microstructure, mechanical properties and machinability of efficiently additive manufactured AISI 316L stainless steel by high-power direct laser deposition / Journal of Materials Processing Technology. 2017. Vol. 240. P. 12 – 22. 13. Êóçíåöîâ Ï. À., Çèñìàí À. À., Ïåòðîâ Ñ. Í., Ãîí÷àðîâ È. Ñ. Ñòðóêòóðà è ìåõàíè÷åñêèå ñâîéñòâà àóñòåíèòíîé ñòàëè 316L, ïîëó÷åííîé ìåòîäîì ñåëåêòèâíîãî ëàçåðíîãî ñïëàâëåíèÿ / Äåôîðìàöèÿ è ðàçðóøåíèå ìàòåðèàëîâ. 2016. ¹ 4. Ñ. 9 – 13. 14. Di W., Changhui S., Yongqiang Y., Yuchao B. Investigation of crystal growthmechanism during selective laser melting and mechanical property characterization of 316L stainless steel parts / Materials and Design. 2016. Vol. 100. P. 291 – 299. 15. Mingming M., Zemin W., Dengzhi W., Xiaoyan Z. Control of shape and performance for direct laser fabrication of precision large-scale metal parts with 316L Stainless Steel / Optics & Laser Technology. 2013. Vol. 45. P. 209 – 216. 16. À. ñ. 2016660262 RU. Ïðîãðàììà óïðàâëåíèÿ ïðîöåññîì âûðàùèâàíèÿ ìåòàëëè÷åñêèõ èçäåëèé àääèòèâíûì ìåòîäîì íà óñòàíîâêå ëàçåðíîé íàïëàâêè / Ãîðóíîâ À. È.; ïðàâîîáëàäàòåëü Êàçàíñêèé íàöèîíàëüíûé èññëåäîâàòåëüñêèé òåõíè÷åñêèé óíèâåðñèòåò èì. À. Í. Òóïîëåâà — ÊÀÈ (ÊÍÈÒÓÊÀÈ). — ¹ 2016617644; çàÿâë. 09.09.2016; îïóáë. 20.10.2016. 17. Ãðÿçíîâ Ì. Þ., Øîòèí Ñ. Â., ×óâèëüäååâ Â. Í. Ýôôåêò ìåçîñòðóêòóðíîãî óïðî÷íåíèÿ ñòàëè 316L ïðè ïîñëîéíîì ëàçåðíîì ñïëàâëåíèè / Âåñòíèê Íèæåãîðîäñêîãî óíèâåðñèòåòà èì. Í. È. Ëîáà÷åâñêîãî. 2012. ¹ 5(1). Ñ. 45 – 50. 18. Ãîðóíîâ À. È. Èçó÷åíèå âëèÿíèÿ òåðìè÷åñêîé îáðàáîòêè íà ñòðóêòóðó è ñâîéñòâà îáðàçöîâ, ïîëó÷àåìûõ ìåòîäîì ïðÿìîãî ëàçåðíîãî íàíåñåíèÿ / Öâåòíûå ìåòàëëû. 2016. ¹ 5(881). Ñ. 69 – 74. «Çàâîäcêàÿ ëàáîpàòîpèÿ. Äèàãíîcòèêà ìàòåpèàëîâ». 2018. Òîì 84. ¹ 1(I) 19. Yang L., Yongqiang Y., Shuzhen M., Di W., Changhui S. Investigation into spatter behavior during selective laser melting of AISI 316L stainless steel powder / Materials and Design. 2015. Vol. 87. P. 797 – 806. 20. Ãîðóíîâ À. È. Èññëåäîâàíèå ñòðóêòóðû è ìåõàíè÷åñêèõ ñâîéñòâ ïîêðûòèÿ èç êîððîçèîííî-ñòîéêîé ñòàëè, ñôîðìèðîâàííîãî ìåòîäîì ãàçîäèíàìè÷åñêîãî íàïûëåíèÿ ñ àêòèâàöèåé ïðîöåññà ëàçåðíûì èçëó÷åíèåì / Äåôîðìàöèÿ è ðàçðóøåíèå ìàòåðèàëîâ. 2016. ¹ 9. Ñ. 2 – 7. 21. ÃÎÑÒ 2789–73. Øåðîõîâàòîñòü ïîâåðõíîñòè. Ïàðàìåòðû è õàðàêòåðèñòèêè. — Ì.: Ñòàíäàðòèíôîðì, 2006. — 7 ñ. 11. 12. 13. REFERENCES 1. Kablov E. N. Additive technologies — the dominant of the national technological initiative / Intellekt Tekhnol. 2015. N 2(11). P. 52 – 55 [in Russian]. 2. Grigor’ev S. N., Smurov I. Yu. Prospects for the development of innovative additive production in Russia and abroad / Innovatsii. 2013. N 10. P. 76 – 82 [in Russian]. 3. Kablov E. N. Strategic directions of development of materials and technologies for their processing for the period up to 2030 / Aviats. Mater. Tekhnol. 2012. N 5. P. 7 – 17 [in Russian]. 4. Grigor’yants A. G., Shiganov I. N., Misyurov A. I. Technological processes of laser processing. — Moscow: Izd. MGTU im. N. É. Baumana, 2006. — 664 p. [in Russian]. 5. Turichin G., Zemlyakov E., Pozdeeva E., Tuominen Ya. Technological possibilities of laser surfacing using high-power fiber lasers / Metalloved. Termich. Obrab. Met. 2012. N 3. P. 35 – 40 [in Russian]. 6. Gorynin I. V., Oryshchenko A. S., Malyshevskii V. A., Farmakovskii B. V., Kuznetsov P. A. Additive technologies on the basis of composite nanomaterials / Metalloved. Termich. Obrab. Met. 2014. N 10(712). P. 4 – 8 [in Russian]. 7. Sova A., Grigoriev S., Okunkova A., Smurov I. Cold spray deposition of 316L stainless steel coatings on aluminium surface with following laser post-treatment / Surface and Coatings Technology. 2013. Vol. 235. P. 283 – 289. 8. Gorunov A. I. Creation of coatings and bulk products from a nickel-based material by the method of additive laser treatment / Metally. 2016. N 1. P. 101 – 105 [in Russian]. 9. Gorunov A. I., Gilmutdinov A. Kh. Study of the effect of heat treatment on the structure and properties of the specimens obtained by the method of direct metal deposition / The International Journal of Advanced Manufacturing Technology. 2016. Vol. 86. Issue 9. P. 2567 – 2574. 10. Luo K., Jing X., Sheng J., Sun G., Yan Z., Lu J. Characterization and analyses on micro-hardness, residual stress and 14. 15. 16. 17. 18. 19. 20. 21. 35 microstructure in laser cladding coating of 316L stainless steel subjected to massive LSP treatment / Journal of Alloys and Compounds. 2016. Vol. 673(15). P. 158 – 169. Gorunov A. I., Gilmutdinov A. Kh. Investigation of coatings of austenitic steels produced by supersonic laser deposition / Optics & Laser Technology. 2017. Vol. 88. P. 157 – 160. Peng G., Bin Z., Chuanzhen H., Huabing G. Study on microstructure, mechanical properties and machinability of efficiently additive manufactured AISI 316L stainless steel by high-power direct laser deposition / Journal of Materials Processing Technology. 2017. Vol. 240. P. 12 – 22. Kuznetsov P. A., Zisman A. A., Petrov S. N., Goncharov I. S. Structure and mechanical properties of 316L austenitic steel obtained by selective laser fusion / Deform. Razrush. Mater. 2016. N 4. P. 9 – 13 [in Russian]. Di W., Changhui S., Yongqiang Y., Yuchao B. Investigation of crystal growthmechanism during selective laser melting and mechanical property characterization of 316L stainless steel parts / Materials and Design. 2016. Vol. 100. P. 291 – 299. Mingming M., Zemin W., Dengzhi W., Xiaoyan Z. Control of shape and performance for direct laser fabrication of precision large-scale metal parts with 316L Stainless Steel / Optics & Laser Technology. 2013. Vol. 45. P. 209 – 216. A. s. 2016660262 RU. Program for controlling the process of growing metal products by an additive method in a laser welding setup / Gorunov A. I.; owner KAI (KNITU — KAI). — N 2016617644; appl. 09.09.2016; publ. 20.10.2016 [in Russian]. Gryaznov M. Yu., Shotin S. V., Chuvil’deev V. N. The effect of mesostructural hardening of 316L steel with layer-by-layer laser fusion / Vestn. Nizhegorod. Univ. im. N. I. Lobachevskogo. 2012. N 5(1). P. 45 – 50 [in Russian]. Gorunov A. I. Study of the influence of heat treatment on the structure and properties of samples obtained by direct laser deposition / Tsvet. Met. 2016. N 5(881). P. 69 – 74 [in Russian]. Yang L., Yongqiang Y., Shuzhen M., Di W., Changhui S. Investigation into spatter behavior during selective laser melting of AISI 316L stainless steel powder / Materials and Design. 2015. Vol. 87. P. 797 – 806. Gorunov A. I. Investigation of the structure and mechanical properties of a coating made of corrosion-resistant steel formed by the method of gas-dynamic spraying with activation of the process by laser radiation / Deform. Razrush. Mater. 2016. N 9. P. 2 – 7 [in Russian]. RF State Standard GOST 2789–73. Surface roughness. Parameters and characteristics. — Moscow: Standartinform, 2006. — 7 p. [in Russian].
