INFLUENCE OF SURFACE MORPHOLOGY ON THE MICROHARDNESS OF ELECTROLESS Ni-B DEPOSIT REVEALED BY AFM OBSERVATION

Introduction　　 Electroless Ni- B alloy has many advantagessuch as superior hardness,excellent wear- resis-tance and some special electrical and magneticproperties[1,2 ] . It can be prepared with eitherDimethylamineborane( DMAB) or sodium borohy-dride as reductant[3 ,4] .The deposits with lowerboron contentwhich are mainly applied to electron-ic industry[5] are prepared by DMAB.While sodi-um borohydride can bring about higher boron con-tent deposits which are chiefly used as wear- resis-…     

INFLUENCE OF SURFACE MORPHOLOGY ON THE MICROHARDNESS OF ELECTROLEESS NI-B DEPOSIT REVEALED BY AFM OBSERVATION

A crystalline and non-crystalline two-phase Ni-B coating was prepared by electroless deposition with potassium borohydride as reducing agent. When the deposit was heated from 10 C to 500 C, it took place three kinds of phase transformation and formed corresponding nickel borides. An Atomic Force Microscopy (AFM) was used to directly view the surface morphologies of the samples in various treated states. The AFM images indicate that nano-dimensional protrusions grow on the surface of the deposit grain during some heat treatment processes,and they are distinguished greatly from the small bulges existing in the as-plated deposit. Further studies show that the microhardness related to the surface topography of thecoating to some extent. Especially when a two-step heat treatment process was performed, the nano-dimensional protrusions on the grain surface grew upt to 40～100nm in diameter and 10～20 nm in height, and the deposit microhardness reached up to HV1500～ 1600 in the meantime.     

STUDY ON ION-POLYMER INTERACTION AND MORPHOLOGIC STRUCTURE OF POLYURETHANE/SALT SYSTEMS

IntroductionRecently,many chemical and physical scien-tists have focused their investigations on solidpolymer electrolytes(SPE) because of their poten-tial applications in high technology fields,includ-ing high energy- density batteries,electrochromicdevices,chemical sensors,smart windows and soon.It is well known that,many factors,such aschemical structure,salt concentration,tempera-ture,morphologic structure,etc.,would have ef-fect on ionic conductive properties of SPE[1,2 ] .Inorder to ob…     

ZnO薄膜PLD过程的机理及实验研究

讨论脉冲激光沉积原理,利用PLD在Si(001)衬底上生长ZnO薄膜,利用X射线衍射(XRD),原子力显微镜(AFM)等测试手段研究了不同衬底温度所生长的ZnO薄膜结构特征和性能。研究表明:衬底温度影响ZnO薄膜结构和性能。在500℃￣600℃沉积范围内随着温度升高,ZnO薄膜结构和性能提高。