組織結(jié)構(gòu)的演變
(1. 山東輕工業(yè)學(xué)院 機(jī)械工程學(xué)院，輕工裝備先進(jìn)制造與測(cè)控技術(shù)實(shí)驗(yàn)室，濟(jì)南 250353)
(2. 淄博市新材料研究所，淄博 255040)
摘 要: 用XRD定量分析法并結(jié)合掃描電鏡形貌觀察，研究化學(xué)沉積高磷(13.3%)含量的Ni-W-P鍍層在不同熱處理?xiàng)l件下的晶化程度、晶粒尺寸及晶格應(yīng)變等組織結(jié)構(gòu)的演變規(guī)律。結(jié)果表明：高磷非晶態(tài)鍍層在退火晶化過程中，Ni3P相的體積分?jǐn)?shù)始終高于Ni相的，700 ℃時(shí)，兩相的體積分?jǐn)?shù)之差顯著增大，鍍層仍有殘存的非晶相；在400~500 ℃之間形成的Ni3P的晶粒尺寸大于Ni的；溫度為500~700 ℃時(shí)，Ni相的尺寸大于Ni3P的，但均未超過納米級(jí)。鍍層晶格應(yīng)變表現(xiàn)為隨退火溫度的升高而降低，鍍態(tài)時(shí)晶格應(yīng)變最大。激光晶化處理的非晶態(tài)Ni-W-P鍍層的顯微結(jié)構(gòu)特征介于400~500 ℃之間退火的鍍層晶化特征。隨掃描速度增加，不僅Ni3P晶粒尺寸增大，而且兩相的尺寸差變大。
關(guān)鍵字: 激光晶化；退火晶化；化學(xué)沉積Ni-W-P；晶化程度；晶粒尺寸；晶格應(yīng)變
（School of Mechanical Engineering, Shandong Institute of Light Industry, Ji’nan 250353, China)
(2. Zibo Institute of New Materials, Zibo 255040, China）
Abstract:The evolution of microstructures, in terms of degree of crystallisation, grain size and lattice strain of electroless Ni-W-P coating with high phosphorous (13.3%) content during laser and furnace annealing was investigated by quantitative XRD method and morphological observation of SEM. The results show that, during the annealing crystallization of the amorphous coating, the volume fraction of Ni3P exceeds that of Ni, and the volume fraction difference between the two phases increases remarkably at 700 ℃, but the remaining amorphous phase still exists in the coating. The grain size of Ni3P is larger than that of Ni between 400 ℃ and 500 ℃, the grain size of both phases is reversed above 500−700 ℃ and are in the range of nanoscale. The lattice strain of as-plated deposit is the maximum and decreases with the increase of temperature. The characteristics of microstructures of the coating treated by laser is consistent with the deposit annealed by furnace between 400 ℃ and 500 ℃. The grain size of Ni3P and phases difference increase with the increase of the scanning velocity.
Key words: laser crystallizing; annealing crystallizing; electroless Ni-W-P; crystallisation degree; grain size; lattice strain
