The inspection group is carefully inspecting the working instruction of green laser pointer

With the movement of the spot, inside the part perpendicular to the direction of scanning speed, the cross section goes through a thermal cycle. Gaussian energy equation [4]: where T is temperature, α the thermal diffusivity, qr heat input parts per unit time per unit volume, λ is the part thermal conductivity, t is time. The MFA sh, by K. E.Easterling in 1984 on the temperature of the heat affected zone of laser processing research, mathematical model of the lower temperature of the laser beam center [7]. Application of the model can be theoretically calculated depth of the laser hardened layer, lay a theoretical foundation for the laser phase transition study. The drawing of 200mw laser pointer is kept in the workshop.
T0 initial temperature of the part A of the part surface absorption rate, P is the laser power, a is the diffusion coefficient (a = A / cρ), ρ is the material density, c is the specific heat, r is the radius of the laser beam, t0 (t0 = r2/4a) spread to half the laser bandwidth required time. The laser energy density W = (Aq / s,) t, s = πd2 / 4, s is the area of the laser zone, t = d / v is the time of laser, d is the diameter of the laser beam, v is the scanning speed. Where α is the thermal diffusivity is generally not a fixed value, it depends on the laser coating, laser scanning speed, laser power, processing materials, and chemical composition. The formula can calculate the temperature of the different depths of the lower part of the laser beam center. The green laser pointer agreement will be signed next week.
Continuous heating and cooling rates can be used for the time derivative: the brackets on the first item on behalf of the heating rate, the second term represents the cooling rate. When the surface of reflectivity R, the surface absorption rate of A = (1-R). A is an important parameter to measure the surface coating layer and passed to the laser energy in the material and determine the critical heat of phase transition in the laser hardening process. Generally not constant, depending on the type of surface coating, laser power, scanning speed and the chemical composition of the hardening material. A value is determined, we can determine the laser hardened layer depth of the radiant energy of the laser input can also be calculated [8]. The advantage of green laser pointer price will help the company win the order of green laser pointer .
Where s = πd2 / 4 a laser processing area, t = d/v- surface of the laser material time, a laser beam diameter d, the v-scan speed. (AP / s,) laser treatment of the energy density of the surface. If a rectangular beam, the input energy density can be written as: where d1 and d2 are the width and length of the laser beam. Following formula for the rectangular beam radiation of the laser input calculated as follows: where b is a rectangular beam along the length of the scanning direction of the velocity, v the scanning speed. In order to quickly calculate the hardened layer depth, Wu Gang, the use of non-steady-state heat source solution derived to describe the internal heat cycle when the laser hardening and rapid estimate of the approximate formula of the hardened layer depth xd [9]. The inspection group is carefully inspecting the working instruction of green laser pointer.
Where q a laser power density, a-diffusion coefficient, k the thermal conductivity, v a scanning speed, b a scan length θAc1 = TAc1-T ∞ - corresponding to the phase transition temperature rise. K. - K.Yoon, W.-B.Kim, S.-J.Na, using the finite element method is laser machined surface heat flow, thermal stress and deformation analysis. The finite element equation for heat conduction problems can write the following equation [5]: where [C] heat conduction matrix, [K] a stiffness matrix, [F] a thermal load vector, [T] node temperature vector. The finite element model, in the laser beam below the fine mesh some, some of far away from the laser beam mesh coarse. The expert group will start the manufacture supervision of green laser pointer in the workshop tomorrow.