【摘要】：利用高速電弧噴涂制備耐熱耐磨涂層對(duì)鍋爐受熱面進(jìn)行防護(hù)具有明顯的優(yōu)勢(shì)。然而目前在工程中為避免噴涂層開(kāi)裂和剝落問(wèn)題,通常采用Ni-Mo或Ni-Al合金打底加耐熱耐磨工作層的噴涂工藝。從而使得材料成本較高和施工工藝比較復(fù)雜。本文針對(duì)此問(wèn)題,設(shè)計(jì)并分別試制了Fe/Cr系、Fe BCrAlNi/B_4C系、FeCrBSi(Mo/W)系、FeCrMoWCuNiAl(Co)/B_4C系等四類(lèi)鐵基粉芯絲材。采用高速電弧噴涂設(shè)備對(duì)其直接在Q235基材上進(jìn)行噴涂。試驗(yàn)結(jié)果表明:四類(lèi)絲材所制備的涂層均成型良好,宏觀(guān)無(wú)裂紋和剝落現(xiàn)象。為探究涂層成分、組織與性能之間的關(guān)系,對(duì)涂層的硬度、抗熱震性能、耐高溫氧化性能、耐摩擦及沖蝕磨損性能進(jìn)行了測(cè)試,并運(yùn)用光學(xué)顯微鏡、掃描電子顯微鏡(SEM)及附屬能譜儀(EDS)、X射線(xiàn)衍射儀(XRD)、同步熱分析儀等測(cè)試手段等對(duì)涂層組織、成分進(jìn)行了分析。研究表明,所有涂層均呈良好的典型層狀結(jié)構(gòu)。Fe/Cr系金屬涂層的平均硬度在503.60~594.56 HV_(0.1)之間,其涂層的硬度和抗氧化性能隨Cr含量增加而提高。其中Cr含量為25%的Fe/Cr系涂層抗高溫氧化性能最好。在FeBCrAlNi/B_4C系中,B_4C可顯著提高其涂層硬度。當(dāng)B_4C含量由0%添加至6%時(shí),涂層平均硬度從786.82 HV_(0.1)上升至1006.58 HV_(0.1)。但當(dāng)B_4C含量增加到9%時(shí),發(fā)現(xiàn)涂層硬度下降為741.45 HV_(0.1)。該類(lèi)涂層均表現(xiàn)出較好的抗熱震性能和耐高溫沖蝕磨損性能。在FeCrBSi(Mo/W)系涂層中均發(fā)現(xiàn)存在一定量的非晶相,涂層平均硬度在646.95~910.37 HV_(0.1)之間,其中FeCrBSiW(WC)涂層組織最為致密,非晶相含量最高為24%,晶化溫度為513.9℃,平均硬度最高。說(shuō)明FeCrBSiW在噴涂條件下非晶形成能力較強(qiáng)。且其抗熱震性能、耐滑動(dòng)摩擦及高溫沖蝕磨損性能較好。但該系涂層抗高溫氧化性能較低。所試驗(yàn)的FeCrMoWCuNiAl類(lèi)高熵合金復(fù)合涂層硬度均較低,在415.87~685.29 HV_(0.1)之間。并且熱震性能和抗高溫氧化性能較差。
[Abstract]:The heat resistant and wear resistant coating prepared by high speed arc spraying has obvious advantages in the protection of boiler heating surface. However, in order to avoid cracking and spalling of coating in engineering, Ni-Mo or Ni-Al alloy is usually used to underlay and heat resistant working layer. As a result, the material cost is high and the construction process is more complicated. In order to solve this problem, four kinds of iron-base powder core wires such as Fe/Cr system, Fe BCrAlNi/B_4C system, FeCrBSi (Mo/W) system, FeCrMoWCuNiAl (Co) / BSP 4C system are designed and manufactured respectively in this paper. High-speed arc spraying equipment was used to spray Q235 substrate directly. The experimental results show that the coatings prepared by the four kinds of wires are well formed, and there is no crack and exfoliation in macroscopic. In order to explore the relationship between the composition, microstructure and properties of the coating, the hardness, thermal shock resistance, high temperature oxidation resistance, friction resistance and erosion wear resistance of the coating were tested, and the optical microscope was used. The microstructure and composition of the coating were analyzed by means of scanning electron microscope (SEM) and (EDS), X ray diffractometer (XRD),). The results show that all the coatings have a typical layered structure. The average hardness of Fe/Cr coatings is between 503.60 and 594.56 HV_, and the hardness and oxidation resistance of the coatings increase with the increase of Cr content. The Fe/Cr coating with 25% Cr content has the best oxidation resistance at high temperature. In the FeBCrAlNi/B_4C system, the hardness of the coating can be significantly increased by Bs4C. The average hardness of the coating increased from 786.82 HV_ (0.1) to 1006.58 HV_ (0.1) when the content of B _ 4C was increased from 0% to 6%. However, the hardness of the coating decreased to 741.45 HV_ (0. 1) when the content of B _ 4 C increased to 9. The coatings show good thermal shock resistance and high temperature erosion wear resistance. A certain amount of amorphous phase was found in FeCrBSi (Mo/W) coating. The average hardness of the coating was between 646.95 and 910.37 HV_ (0.1). The microstructure of FeCrBSiW (WC) coating was the most compact, and the content of amorphous phase was 24%. The crystallization temperature is 513.9 鈩，

本文編號(hào)：2358967